Description:TECHNICAL FIELD
[0001] The present disclosure pertains to the technical field of Ziegler-Natta catalysts. In particular, the present disclosure provides a Ziegler-Natta catalyst comprising isohexide derivatives of formula I as internal electron donor and a method for preparation thereof,

wherein R1 and R2, independent of each other, is selected from C6 to C12 aryl group, and C6 to C12 heteroaryl group.

BACKGROUND
[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[0003] Among polyolefin resins, polypropylene (PP) is one of the largest in demand in the world market due to its high performance characteristics such as stiffness, impact resistance, transparency, low production cost and ability to be recycled. These properties make it an extremely versatile polymer, which can be applied in various market segments such as industrial packaging, automotive, adhesives and molded products.
[0004] Usually MgCl2 supported Titanium catalysts are used as catalyst for the production of polypropylene and internal donors (ID) are used to get a significant increase in the isotacticity of the polypropylene. Modern MgCl2-supported Ziegler-Natta catalyst usually consists of TiCl4 as an active species and an internal donor as an isotacticity improver, and MgCl2 as a support. Internal donors play a prominent role in catalyst performance and affect the catalyst reactivity and the PP properties such as isotacticity, molecular weight, and its distribution. Commonly these electron donors are phthalates, 1,3-diethers, malonates, succinates, glutarates, maleates, and ketoesters. Industrially, most of the time Phthalate based catalysts have been widely used for the commercial production of PP. Use of alkoxy-silane as an external donors led to further increase in performance of these catalyst systems.
[0005] Phthalate based systems have caused regulatory and human health concern, therefore it is important to find suitable alternatives. For the production of medical grade PP, food grade PP, the phthalate free catalyst system should be employed and because of these reasons, the research in the field of phthalate free catalyst system development has boosted in the last two decades. Non-phthalate systems have been evaluated in the literature and found that they generally do not match the performance of the phthalate systems. Hence, it is very important to improve the technology of non-phthalate systems to overcome the barriers. Phthalate-based systems can be considered as a very important catalyst system but due to human health concerns, several industries are working on the development of phthalate free catalyst systems for the production of PP. Few state of the art catalysts have been summarized hereinbelow.
[0006] US 9284392 B2 discloses solid catalyst component for olefin polymerization. The solid catalyst component comprises titanium, magnesium, halogen and a combination of internal electron donor compounds containing at least one 1,8-naphthyl diester compound and at least one 3,3-bis(methoxymethyl) alkane compound. Another US 20080214881 A1 discloses solid, hydrocarbon-insoluble, catalyst component useful in polymerizing olefins containing magnesium, titanium, and halogen, further containing an internal electron donor of specific general formula. US 4971937A discloses catalyst components for the polymerization of olefins and modified with electron-donor compounds, comprising a titanium halide supported on a magnesium dihalide in active form and containing as an electron-donor compound a di- or other polyether having specific reactivity characteristics towards MgCl2 and TiCl4.
[0007] It is, therefore, a long standing need in the art to provide improved internal electron donors that overcome the shortcomings of the conventional catalyst systems. Need is also felt for improved Ziegler-Natta catalysts and method for preparation thereof. The present disclosure fulfils the existing need, at least in part, and provides new internal electron donors, method of production thereof, improved Ziegler-Natta catalysts as well as method for preparation thereof.
[0008] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.

OBJECTS
[0009] An object of the present disclosure is to provide internal electron donors that overcome the shortcomings of the conventional internal electron donors in Ziegler-Natta catalysts.
[0010] Another object of the present disclosure is to provide a method for production of internal electron donors.
[0011] Yet another object of the present disclosure is to provide Ziegler-Natta catalysts that overcome the shortcomings of the conventional Ziegler-Natta catalysts.
[0012] Further object of the present disclosure is to provide Ziegler-Natta catalyst that is non-toxic, environment friendly and commercially viable.
[0013] Still further object of the present disclosure is to provide a method of production of Ziegler-Natta catalysts.
[0014] Still further object of the present disclosure is to provide a method for preparing polypropylene that is non-toxic, environment friendly and commercially viable.

SUMMARY
[0015] The present disclosure pertains to the technical field of Ziegler-Natta catalysts. In particular, the present disclosure provides a Ziegler-Natta catalyst comprising isohexide derivatives of formula I as internal electron donor and a method for preparation thereof.
[0016] An aspect of the present disclosure relates to a method for preparing a Ziegler-Natta catalyst, said method comprising at least the step of mixing a magnesium support with a transition metal halide in presence of an internal donor compound of formula I or an isomer or mixtures thereof:

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12aryl group, and C6 to C12heteroaryl group.
[0017] In an embodiment, R1 and R2in the internal donor compound of formula I, independent of each other, are selected from methyl and phenyl.
[0018] In another embodiment, the magnesium support is selected from MgCl2 and an adduct MgCl2.mR3OH, wherein R3 represents linear or branched alkyl group with 1 to 12 carbon atoms, and m ranges between 1 to 6.
[0019] In still another embodiment, the step of mixing comprises: (a) mixing MgCl2 with an alcohol of formula R3OH at a temperature ranging from 50°C to 150°C in presence of the internal donor compound of formula I or isomer or mixtures thereof to obtain an internal donor treated magnesium support, wherein R3 represents linear or branched alkyl group with 1 to 12 carbon atoms; and (b) mixing the internal donor treated magnesium support from step (a) with the transition metal halide at a temperature ranging from 50°C to 150°C to obtain the Ziegler-Natta catalyst. The substituent R3 in the alcohol of formula R3OH is ethyl group, and wherein the transition metal halide is titanium halide.
[0020] In yet another embodiment, the step of mixing comprises:(a) mixing the magnesium support with the transition metal halide at a temperature ranging from 50°C to 150°C to obtain a reaction mixture; and (b) adding the internal donor compound of formula I or the isomer or mixtures thereof to the reaction mixture of step (a) at a temperature ranging from 50°C to 150°C to obtain the Ziegler-Natta catalyst.
[0021] In another embodiment, the internal donor compound of formula I is selected from a compound having formula Ia or formula Ib:

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12aryl group, and C6 to C12 heteroaryl group.
[0022] In a further embodiment, the internal donor compound is selected from: Isosorbide benzoic ester (ISBE), Isosorbide acetic ester (ISAE), Isomannide benzoic ester (IMBE) and Isomannide acetic ester (ISAE) having the following structures:
,
, and .
[0023] Another aspect of the present disclosure provides a Ziegler-Natta catalyst. The catalyst comprises: (a) an internal donor compound of formula I or an isomer or mixtures thereof

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12aryl group, and C6 to C12heteroaryl group; (b) a transition metal halide; and (c) a magnesium support.
[0024] In an embodiment, R1 and R2 in the internal donor compound of formula I, independent of each other, are selected from methyl and phenyl.
[0025] In another embodiment, the magnesium support is selected from MgCl2 and an adduct MgCl2.mR3OH, wherein R3 represents linear or branched alkyl group with 1 to 12 carbon atoms, and m ranges between 1 to 6. The substituent R in the alcohol of formula ROH is ethyl group, whereas the transition metal halide is titanium halide.
[0026] In yet another embodiment, the internal donor compound of formula I is selected from a compound having formula Ia or formula Ib:

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12 aryl group, and C6 to C12 heteroaryl group.
[0027] In still another embodiment, the internal donor compound is selected from: Isosorbide benzoic ester (ISBE), Isosorbide acetic ester (ISAE), Isomannide benzoic ester (IMBE) and Isomannide acetic ester (ISAE) having the following structures:
,
, and .
[0028] Further aspect of the present disclosure relates to a method for preparing polyolefin obtained from olefin polymerization in presence of the above Ziegler-Natta catalyst.
[0029] Still further aspect of the present disclosure provides a polyolefin obtained from the above method.
[0030] Still further aspect of the present disclosure provides a compound of formula I or an isomer or mixtures thereof:

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12 aryl group, and C6 to C12 heteroaryl group.
[0031] Still further aspect of the present disclosure is drawn towards use of a compound of formula I or an isomer or mixtures thereof as internal electron donor in Ziegler-Natta catalysts:

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12aryl group, and C6 to C12heteroaryl group.
[0032] Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS
[0033] The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.
[0034] FIG. 1A-1C illustrate exemplary FTIR spectra,1H-NMR spectra and 13C-NMR spectra of Isosorbide benzoate ester (ISBE), realized in accordance with an embodiment of the present disclosure.
[0035] FIG. 2 illustrates an exemplary FTIR spectra of Isosorbide acetate ester (ISAE), realized in accordance with another embodiment of the present disclosure.
[0036] FIG. 3A-3C illustrate exemplary FTIR spectra, 1H-NMR spectra and 13C-NMR spectra of IMBE, realized in accordance with an embodiment of the present disclosure.
[0037] FIG. 4 illustrates an exemplary FTIR spectra of catalyst 1 (Cat 1), prepared in accordance with an embodiment of the present disclosure.
[0038] FIG. 5 illustrates an exemplary SEM image of catalyst 1 (Cat 1), prepared in accordance with an embodiment of the present disclosure.
[0039] FIG. 6 illustrates an exemplary SEM image of catalyst 2 (Cat 2), prepared in accordance with an embodiment of the present disclosure.
[0040] FIG. 7 illustrates an exemplary FTIR spectra of catalyst 6 (Cat 6), prepared in accordance with an embodiment of the present disclosure.
[0041] FIG. 8 illustrates an exemplary FTIR spectra of catalyst 7 (Cat 7), prepared in accordance with an embodiment of the present disclosure.
[0042] FIG. 9A-9C illustrate exemplary SEM images of polypropylene, prepared in accordance with embodiments of the present disclosure.
[0043] FIG. 10A-10D illustrate exemplary Powder XRD data pertaining to the polypropylene, realized in accordance with embodiments of the present disclosure.
[0044] FIG. 11A-11C illustrate exemplary SEM images of the resultant polyethylene, prepared in accordance with embodiments of the present disclosure.
[0045] FIG. 12A-12C illustrate exemplary Powder XRD data pertaining to the resultant polyethylene, realized in accordance with embodiments of the present disclosure.

DETAILED DESCRIPTION
[0046] The following is a detailed description of various aspects and embodiments of the present invention. The aspects and embodiments are in such detail as to clearly communicate the invention. However, the amount of detail offered is not intended to limit the anticipated variations of these aspects and embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.
[0047] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the “invention” may in some cases refer to certain specific embodiments only. In other cases it will be recognized that references to the “invention” will refer to subject matter recited in one or more, but not necessarily all, of the claims.
[0048] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability.
[0049] Unless the context requires otherwise, throughout the specification which follow, the word “comprise” and variations thereof, such as, “comprises” and “comprising” are to be construed in an open, inclusive sense that is as “including, but not limited to.”
[0050] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
[0051] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[0052] In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term “about.”. Accordingly, in some embodiments, the numerical parameters set forth in the written description are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable.
[0053] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein.
[0054] The headings and abstract of the invention provided herein are for convenience only and do not interpret the scope or meaning of the embodiments.
[0055] All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[0056] The following description provides many exemplary embodiments of the inventive subject matter. Although, each embodiment represents a single combination of inventive elements, the inventive subject matter is considered to include all possible combinations of the disclosed elements. Thus, if one embodiment comprises elements A, B, and C, and a second embodiment comprises elements B and D, then the inventive subject matter is also considered to include other remaining combinations of A, B, C, or D, even if not explicitly disclosed.
[0057] Various terms as used herein are shown below. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.
[0058] The present disclosure pertains to the technical field of Ziegler-Natta catalysts. In particular, the present disclosure provides a Ziegler-Natta catalyst comprising isohexide derivatives of formula I as internal electron donor and a method for preparation thereof.
[0059] An aspect of the present disclosure relates to a process for a Ziegler-Natta catalyst, said method comprising at least the step of mixing a magnesium support with a transition metal halide in presence of an internal donor compound of formula I or an isomer or mixtures thereof:

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12 aryl group, and C6 to C12 heteroaryl group.
[0060] In the present context, the term "alkyl" refers to an alkane absent hydrogen. Further, the term "aryl" refers to a monocyclic or fused bicyclic, aromatic ring assembly. For example, aryl may be phenyl, benzyl or naphthyl. Furthermore, the term "heteroaryl" refers to a monocyclic or polycyclic ring assembly wherein at least one ring atom is a heteroatom and the remaining ring atoms are carbon, and at least one of the rings comprising the ring assembly is an aromatic ring.
[0061] In an embodiment, R1 and R2, independent of each other, is selected from linear or branched, substituted or unsubstituted C1 to C7 alkyl group, or C1 to C6 alkyl group, or C1 to C5 alkyl group, or C1 to C4 alkyl group, or C1 to C3 alkyl group.
[0062] In another embodiment, R1 and R2, independent of each other, is selected from branched or unbranched C6 to C12 aryl group, C6 to C10 aryl group, or C6 to C8 aryl group.
[0063] In yet another embodiment, R1 and R2, independent of each other, is selected from branched or unbranched C6 to C12 heteroaryl group, or C6 to C10 heteroaryl group, or C6 to C8 heteroaryl group.
[0064] In still another embodiment, R1 and R2 in the internal donor compound of formula I, independent of each other, is selected from methyl and phenyl.
[0065] In an embodiment, the magnesium support is selected from MgCl2 and an adduct MgCl2.mR3OH. The substituent R3 represents linear or branched, substituted or unsubstituted alkyl group with 1 to 12 carbon atoms, and m ranges between 1 to 6. In an embodiment, R3 represents linear or branched, substituted or unsubstituted alkyl group with 1 to 12 carbon atoms, or 1 to 10 carbon atoms, or 1 to 8 carbon atoms, or 1 to 6 carbon atoms, or 1 to 4 carbon atoms. In another embodiment, R3 is ethyl group.
[0066] In an embodiment, the step of mixing comprises: (a) mixing MgCl2 with an alcohol of formula R3OH at a temperature ranging from 50°C to 150°C in presence of the internal donor compound of formula I or isomer or mixtures thereof to obtain an internal donor treated magnesium support, wherein R3 represents linear or branched alkyl group with 1 to 12 carbon atoms; and (b) mixing the internal donor treated magnesium support from step (a) with the transition metal halide at a temperature ranging from 50°C to 150°C to obtain the Ziegler-Natta catalyst. In an embodiment, R3 in the alcohol of formula R3OH is ethyl group, and wherein the transition metal halide is titanium halide.
[0067] In another embodiment, the step of mixing comprises: (a) contacting anhydrous MgCl2 with a dry alcohol of formula R3OH in presence of a hydrocarbon solvent at a temperature ranging from 80°C to 120°C to produce an adduct MgCl2*mR3OH, wherein R3 represents linear or branched, substituted or unsubstituted alkyl group with 1 to 12 carbon atoms; (b) contacting the adduct MgCl2*mR3OH with the internal donor compound of formula I or the isomer or mixtures thereof at a temperature ranging from 60°C to 120°C to obtain the internal donor treated adduct; and (c) subjecting the internal donor treated adduct from step (b) to titanationone to three times by: contacting the internal donor treated adduct with a titanium halide at a temperature ranging from 90°C to 140°C followed by removal of the titanium halide to obtain the Ziegler-Natta catalyst.
[0068] In an embodiment, R3 represents linear or branched, substituted or unsubstituted alkyl group with 1 to 12 carbon atoms, or 1 to 10 carbon atoms, or 1 to 8 carbon atoms, or 1 to 6 carbon atoms, or 1 to 4 carbon atoms. In another embodiment, R3 is ethyl group.
[0069] In another embodiment, the step of mixing comprises: (a) mixing the magnesium support with the transition metal halide at a temperature ranging from 50°C to 150°C to obtain a reaction mixture; and (b) adding the internal donor compound of formula I or the isomer or mixtures thereof to the reaction mixture of step (a) at a temperature ranging from 50°C to 150°C to obtain the Ziegler-Natta catalyst.
[0070] In one particular embodiment, the step of mixing comprises: (a) contacting anhydrous MgCl2 with a titanium metal halide in presence of a hydrocarbon solvent at a temperature ranging from 90°C to 150°C to obtain the reaction mixture; (b) adding the internal donor compound of formula I or the isomer or mixtures thereof to the reaction mixture of step (a) at a temperature ranging from 90°C to 150°C; and optionally, (c) subjecting the mixture from step (b) to titanation one to three times by contacting the mixture from step (b) with titanium metal halide in presence of a hydrocarbon solvent at a temperature ranging from 90°C to 150°C to obtain the Ziegler-Natta catalyst.
[0071] In yet another embodiment, the internal donor compound of formula I is selected from a compound having formula Ia or formula Ib:

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12 aryl group, and C6 to C12 heteroaryl group.
[0072] In still another embodiment, the internal donor compound is selected from: Isosorbide benzoic ester (ISBE), Isosorbide acetic ester (ISAE), Isomannide benzoic ester (IMBE) and Isomannide acetic ester (ISAE) having the following structures:
,
, and

[0073] Another aspect of the present disclosure provides a Ziegler-Natta catalyst. In an embodiment, the Ziegler-Natta catalyst comprises: (a) an internal donor compound of formula I or an isomer or mixtures thereof

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12 aryl group, and C6 to C12 heteroaryl group;
(b) a transition metal halide; and
(c) a magnesium support.
[0074] In another embodiment, the Ziegler-Natta catalyst is obtained from the method described hereinabove. Accordingly, the embodiments pertaining to the method for preparing the Ziegler-Natta catalyst are applicable herein as well.
[0075] In an embodiment, R1 and R2, independent of each other, is selected from linear or branched, substituted or unsubstituted C1 to C7 alkyl group, or C1 to C6 alkyl group, or C1 to C5 alkyl group, or C1 to C4 alkyl group, or C1 to C3 alkyl group.
[0076] In another embodiment, R1 and R2, independent of each other, is selected from branched or unbranched C6 to C12 aryl group, C6 to C10 aryl group, or C6 to C8 aryl group.
[0077] In yet another embodiment, R1 and R2, independent of each other, is selected from branched or unbranched C6 to C12 heteroaryl group, or C6 to C10 heteroaryl group, or C6 to C8 heteroaryl group.
[0078] In still another embodiment, R1 and R2 in the internal donor compound of formula I, independent of each other, is selected from methyl and phenyl.
[0079] In an embodiment, the magnesium support is selected from MgCl2 and an adduct MgCl2.mR3OH. The substituent R3 represents linear or branched, substituted or unsubstituted alkyl group with 1 to 12 carbon atoms, and m ranges between 1 to 6. In an embodiment, R3 represents linear or branched, substituted or unsubstituted alkyl group with 1 to 12 carbon atoms, or 1 to 10 carbon atoms, or 1 to 8 carbon atoms, or 1 to 6 carbon atoms, or 1 to 4 carbon atoms. In another embodiment, R3 is ethyl group.
[0080] In yet another embodiment, the internal donor compound of formula I is selected from a compound having formula Ia or formula Ib:

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12 aryl group, and C6 to C12 heteroaryl group.
[0081] In still another embodiment, the internal donor compound is selected from: Isosorbide benzoic ester (ISBE), Isosorbide acetic ester (ISAE), Isomannide benzoic ester (IMBE) and Isomannide acetic ester (ISAE) having the following structures:
,
, and .

[0082] Further aspect of the present disclosure provides an internal donor compound of formula I or an isomer or mixtures thereof for Ziegler-Natta catalysts,

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12 aryl group, and C6 to C12 heteroaryl group.
[0083] In an embodiment, R1 and R2, independent of each other, is selected from linear or branched, substituted or unsubstituted C1 to C7 alkyl group, or C1 to C6 alkyl group, or C1 to C5 alkyl group, or C1 to C4 alkyl group, or C1 to C3 alkyl group.
[0084] In another embodiment, R1 and R2, independent of each other, is selected from branched or unbranched C6 to C12 aryl group, C6 to C10 aryl group, or C6 to C8 aryl group.
[0085] In yet another embodiment, R1 and R2, independent of each other, is selected from branched or unbranched C6 to C12 heteroaryl group, or C6 to C10 heteroaryl group, or C6 to C8 heteroaryl group.
[0086] In still another embodiment, R1 and R2 in the internal donor compound of formula I, independent of each other, is selected from methyl and phenyl.
[0087] In an embodiment, the magnesium support is selected from MgCl2 and an adduct MgCl2.mR3OH. The substituent R3 represents linear or branched, substituted or unsubstituted alkyl group with 1 to 12 carbon atoms, and m ranges between 1 to 6. In an embodiment, R3 represents linear or branched, substituted or unsubstituted alkyl group with 1 to 12 carbon atoms, or 1 to 10 carbon atoms, or 1 to 8 carbon atoms, or 1 to 6 carbon atoms, or 1 to 4 carbon atoms. In another embodiment, R3 is ethyl group.
[0088] In yet another embodiment, the internal donor compound of formula I is selected from a compound having formula Ia or formula Ib:

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12 aryl group, and C6 to C12 heteroaryl group.
[0089] In still another embodiment, the internal donor compound is selected from: Isosorbide benzoic ester (ISBE), Isosorbide acetic ester (ISAE), Isomannide benzoic ester (IMBE) and Isomannide acetic ester (ISAE) having the following structures:
,
, and .
[0090] Still further aspect of the present disclosure is drawn towards use of a compound of formula I as internal electron donor for preparation of a Ziegler-Natta catalyst,

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12aryl group, and C6 to C12 heteroaryl group.
[0091] In an embodiment, R1 and R2, independent of each other, is selected from linear or branched, substituted or unsubstituted C1 to C7 alkyl group, or C1 to C6 alkyl group, or C1 to C5 alkyl group, or C1 to C4 alkyl group, or C1 to C3 alkyl group.
[0092] In another embodiment, R1 and R2, independent of each other, is selected from branched or unbranched C6 to C12 aryl group, C6 to C10 aryl group, or C6 to C8 aryl group.
[0093] In yet another embodiment, R1 and R2, independent of each other, is selected from branched or unbranched C6 to C12 heteroaryl group, or C6 to C10 heteroaryl group, or C6 to C8 heteroaryl group.
[0094] In still another embodiment, R1 and R2 in the internal donor compound of formula I, independent of each other, is selected from methyl and phenyl.
[0095] In an embodiment, the magnesium support is selected from MgCl2 and an adduct MgCl2.mR3OH. The substituent R3 represents linear or branched, substituted or unsubstituted alkyl group with 1 to 12 carbon atoms, and m ranges between 1 to 6. In an embodiment, R3 represents linear or branched, substituted or unsubstituted alkyl group with 1 to 12 carbon atoms, or 1 to 10 carbon atoms, or 1 to 8 carbon atoms, or 1 to 6 carbon atoms, or 1 to 4 carbon atoms. In another embodiment, R3 is ethyl group.
[0096] In yet another embodiment, the internal donor compound of formula I is selected from a compound having formula Ia or formula Ib:

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12 aryl group, and C6 to C12 heteroaryl group.
[0097] In still another embodiment, the internal donor compound is selected from: Isosorbide benzoic ester (ISBE), Isosorbide acetic ester (ISAE), Isomannide benzoic ester (IMBE) and Isomannide acetic ester (ISAE) having the following structures:
,
, and .
[0098] Still further aspect of the present disclosure relates to a method for preparing polyolefin obtained from olefin polymerization in presence of the Ziegler-Natta described hereinabove.
[0099] In an embodiment, the Ziegler-Natta catalyst for olefin polymerization is obtained from the method described hereinabove. Accordingly, the embodiments pertaining to the Ziegler-Natta catalyst are applicable herein as well.
[00100] Still further aspect of the present disclosure provides a polyolefin obtained from the method described hereinabove.
[00101] In an embodiment, the polyolefin is obtained from the method described hereinabove. Accordingly, the embodiments pertaining to the method are applicable herein as well.
[00102] Yet another aspect of the present disclosure relates to a compound of formula I or an isomer or mixtures thereof:

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12aryl group, and C6 to C12heteroaryl group.
[00103] In an embodiment, the compound of formula I or the isomer or mixtures thereof is same as the internal donor compound of formula I or the isomer or mixtures thereof as described hereinabove. Accordingly, the various embodiments pertaining to the internal donor compound of formula I or the isomer or mixtures thereof described hereinabove are applicable here as well.
[00104] Still further aspect of the present disclosure is drawn towards use of a compound of formula I or an isomer or mixtures thereof as internal electron donor in Ziegler-Natta catalysts:

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12aryl group, and C6 to C12heteroaryl group.
[00105] In an embodiment, the compound of formula I or the isomer or mixtures thereof is same as the internal donor compound of formula I or the isomer or mixtures thereof as described hereinabove. Accordingly, the various embodiments pertaining to the internal donor compound of formula I or the isomer or mixtures thereof described hereinabove are applicable here as well.
[00106] While the foregoing description discloses various embodiments of the disclosure, other and further embodiments of the invention may be devised without departing from the basic scope of the disclosure. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.
EXAMPLES
SYNTHESIS OF INTERNAL ELECTRON DONORS
[00107] Synthesis of Isosorbide benzate ester (ISBE):

[00108] In a clean 250 ml round bottom flask (RBF), benzoic acid (8.35 g, 0.0684 mol) and N,N'-Dicyclohexylcarbodiimide (DCC) (15.51 g, 0.0752 mol) was mixed under nitrogen. Then 70 ml of DCM (dichloromethane) was added followed by DIPA (Di-isopropylamine) (11.77 mL, 0.1163 mol). Reaction mixture was stirred at RT (23 °C) for 30 minutes. Isosorbide (5 g, 0.0341 mol) was added under nitrogen to the above reaction mixture. Immediately the reaction mixture color changed to pale yellow. The above reaction mixture was stirred at room temperature (RT)(about 23°C) for 48 hours. Reaction was quenched with water 950 mL. Organic layer was extracted and dried on sodium sulfate. Solvent was evaporated and solid was diluted again with DCM. Insoluble solid was found to be dicyclohexylurea which was filtered. Soluble fraction was evaporated, dried and characterized. Isosorbide benzoate ester (donor molecule 1) obtained in about 30% yield. Structure of the resultant molecule was established using 1H, 13C-NMR and FTIR analysis. Melting point of isosorbide was found to be 60°C. Melting point of ISBE was found to be 165-168 °C. FTIR spectra, 1H-NMR spectra and 13C-NMR spectra of Isosorbide benzoate ester (ISBE) are provided at FIGs. 1A-1C, respectively.
[00109] Synthesis of Isosorbide acetate ester (ISAE):

[00110] In a clean 250 ml round bottom flask (RBF), acetic acid (3.91 mL, 0.0684 mol) and DCC (15.51 g, 0.0752 mol) was mixed under nitrogen. Then 70 ml of DCM (dichloromethane) was added followed by DIPA (Di-isopropylamine) (11.77 mL, 0.1163 mol). Reaction mixture was stirred at RT (23°C) for 30 minutes. Isosorbide (5 g, 0.0342 mol) was added under nitrogen to the above reaction mixture. Immediately the reaction mixture color changes to pale yellow. The above reaction mixture was stirred at RT for 48 hours. Reaction was quenched with water 950 mL. Organic layer was extracted and dried on sodium sulfate. Solvent was evaporated and solid was diluted with again DCM. Insoluble solid was found to be dicyclohexylurea which was filtered. Soluble fraction was evaporated, dried and characterized. Isosorbide acetate ester (donor molecule 2) obtained in ~ 94% yield. Structure of the resultant molecule was established using 1H, 13C-NMR and FTIR analysis. Melting point of isosorbide was found to be 60 °C. Melting point of ISAE was found to be 110-112 °C. FTIR spectra of Isosorbide acetate ester (ISAE) is provided at FIG. 2.
[00111] Synthesis of Isomannide benzoate ester (IMBE):

[00112] In a clean 250 ml round bottom flask (RBF), benzoic acid (8.35 g, 0.0680 mol) and DCC (15.51 g, 0.0752 mol) was mixed under nitrogen. Then 70 ml of DCM (dichloromethane) was added followed by DIPA (Di-isopropyl amine) (11.77 mL, 0.1163 mol). Reaction mixture was stirred at RT (23 °C) for 30 minutes. Isomannide (5 g, 0.0341 mol) was added under nitrogen to the above reaction mixture. Immediately the reaction mixture color changes to pale yellow. The above reaction mixture was stirred at RT for 48 hours. Reaction was quenched with water 950 mL. Organic layer was extracted and dried on sodium sulfate. Solvent was evaporated and solid was diluted with again DCM. Insoluble solid was found to be dicyclohexylurea which was filtered. Soluble fraction was evaporated, dried and characterized. Isomannide benzoate ester (donor molecule 3) obtained in ~ 43% yield. Structure of the resultant molecule was established using 1H, 13C-NMR and FTIR analysis. Melting Point of isomannide was found to be 80-85 °C. Melting point of IMBE was found to be 109-112°C. FTIR spectra, 1H-NMR spectra and 13C-NMR spectra of IMBE are provided at FIGs. 3A-3C, respectively.
[00113] Synthesis of Isomannide acetate ester (IMAE):

[00114] In a clean 250 ml round bottom flask (RBF), acetic acid (3.91 mL, 0.0680 mol) and DCC (15.51 g, 0.0752 mol) was mixed under nitrogen. Then 70 ml of DCM (dichloromethane) was added followed by DIPA (Di-isopropyl amine) (11.77 mL, 0.1163 mol). Reaction mixture was stirred at RT (23 °C) for 30 minutes. Isomannide (5 g, 0.0341 mol) was added under nitrogen to the above reaction mixture. Immediately the reaction mixture color changes to pale yellow. The above reaction mixture was stirred at RT for 48 hours. Reaction was quenched with water 950 mL. Organic layer was extracted and dried on sodium sulfate. Solvent was evaporated and solid was diluted with again DCM. Insoluble solid was found to be dicyclohexylurea which was filtered. Soluble fraction was evaporated, dried and characterized. Isomannide acetate ester (donor molecule 4) obtained in ~ 38% yield. Structure of the resultant molecule was established using 1H, 13C-NMR and FTIR analysis. Melting Point of isomannide was found to be 80-85 °C. Melting point of Isomannide acetate ester (IMAE) was found to be 121-125 °C.
SYNTHESIS OF ZIEGLER-NATTA CATALYSTS
[00115] COMPARATIVE EXAMPLE - Synthesis of Ziegler-Natta catalyst using Di-isobutylphthalate (DIBP) as internal donor (Cat 1) – using MgCl2.EtOH adduct as support:
[00116] Step 1- MgCl2.EtOH adduct synthesis: Anhydrous MgCl2 (4.76 g) was taken from glove box in a Schlenk RBF and dry ethanol (10 mL) and 50 mL of dry heptane was syringed. The reaction mixture was heated at 100°C for 1 hour and then cool down to 70°C. DIBP internal donor (varying concentration) was added at 70 °C temperature and again reaction temperature was increased to 100 °C and heated for 2 hours. Reaction mixture was cool down to 70°C and 100 mL dry decane was syringed and stirred vigorously. The ethanol was evaporated at 70°C and then the remaining solvents (heptane + decane) was removed by cannula filtration. The solid obtained was washed with heptane (50 mL * 4) and dried under vacuum for 3 hours. The resultant MgCl2.EtOH adduct was used in step 2 for titanation.
[00117] Step 2 - TiCl4 treatment to MgCl2.EtOH adduct: The above adduct from step 1 was taken in 3-neck RBF and TiCl4 (30 mL) was added and reaction mixture was heated to 120°C for 2 hours. The reaction mixture was cooled to 90°C and the TiCl4 was removed by cannula filtration at 90°C temperature. Again TiCl4 was added and the reaction mixture was heated at 120°C for 1 hour and TiCl4 was filtered off at 90°C. The addition and removal of TiCl4 was carried out one more time (total 3 times TiCl4 treatment). Finally, solid was washed with dry heptane (60 mL * 6) and final washing was given by dry hexane (60 mL * 1). The obtained solid catalyst was dried under vacuum for few hours and then Magnesium and Titanium content was determined. FTIR spectra of catalyst 1 (Cat 1) is provided at FIG. 4. SEM image of catalyst 1 (Cat 1) is provided at FIG. 5. Upon ICP-OES analysis of catalyst 1, Mg content was found to be 15.9% and Ti content was found to be 9.4%.
[00118] Synthesis of Ziegler-Natta catalyst using Isosorbide Benzoate Ester (ISBE) as internal donor (Cat 2) – using MgCl2.EtOH adduct assupport
[00119] Step 1 - MgCl2.EtOH adduct synthesis: Anhydrous MgCl2 (4.76 g) was taken from glove box in a Schlenk RBF and dry ethanol (10 mL) and 50 mL of dry heptane was syringed. The reaction mixture was heated at 100°C for 1 hour and then cool down to 70°C. ISBE internal donor (varying concentration) was added at 70°C temperature and again reaction temperature was increased to 100°C and heated for 2 hours. Reaction mixture was cool down to 70°C and 100 mL dry decane was syringed and stirred vigorously. The ethanol was evaporated at 70°C and then the remaining solvents (heptane + decane) was removed by cannula filtration. The solid obtained was washed with heptane (50 mL * 4) and dried under vacuum for 3 hours. The resultant MgCl2.EtOH adduct was used in step 2 for titanation.
[00120] Step 2 - TiCl4 treatment to MgCl2.EtOH adduct: The above adduct from step 1 was taken in a 3-neck RBF and TiCl4 (30 mL) was added and reaction mixture was heated to 120°C for 2 hours. The reaction mixture was cooled to 90°C and the TiCl4 was removed by cannula filtration at 90°C temperature. Again TiCl4 was added and the reaction mixture was heated at 120°C for 1 hour and TiCl4 was filtered off at 90°C. The addition and removal of TiCl4 was carried out one more time (total 3 times TiCl4 treatment). Finally, solid was washed with dry heptane (60 mL * 6) and final washing was given by dry hexane (60 mL * 1). The obtained solid catalyst was dried under vacuum for few hours and then Magnesium and Titanium content was determined. SEM image of catalyst 2 (Cat 2) is provided at FIG. 6. Upon ICP-OES analysis of catalyst 2, Mg content was found to be 13.2% and Ti content was found to be 10.4%.
[00121] Synthesis of Ziegler-Natta catalyst using Isosorbide Acetate Ester (ISAE) as internal donor (Cat 3) – using MgCl2.EtOH adduct as support
[00122] Step 1 - MgCl2.EtOH adduct synthesis: Anhydrous MgCl2 (4.76 g) was taken from glove box in a Schlenk RBF and dry ethanol (10ml) and 50 mL of dry heptane was syringed. The reaction mixture was heated at 100 °C for 1 hour and then cool down to 70 °C. ISAE internal donor (varying concentration) was added at 70°C temperature and again reaction temperature was increased to 100°C and heated for 2 hours. Reaction mixture was cool down to 70°C and 100 mL dry Decane was syringed and stirred vigorously. The ethanol was evaporated at 70°C and then the remaining solvents (heptane + decane) was removed by cannula filtration. The solid obtained was washed with heptane (50 mL * 4) and dried under vacuum for 3 hours. The resultant MgCl2.EtOH adduct was used in step 2 for titanation.
[00123] Step 2 - TiCl4 treatment to MgCl2.EtOH adduct: The above adduct from step 1 was taken in a 3-neck RBF and TiCl4 (30ml) was added and reaction mixture was heated to 120 °C for 2 hours. The reaction mixture was cooled to 90 °C and the TiCl4 was removed by cannula filtration at 90 °C temperature. Again TiCl4 was added and the reaction mixture was heated at 120 °C for 1 hour and TiCl4 was filtered off at 90 °C. The addition and removal of TiCl4 was carried out one more time (total 3 times TiCl4 treatment). Finally, solid was washed with dry heptane (60 mL * 6) and final washing was given by dry hexane (60 mL * 1). The obtained solid catalyst was dried under vacuum for few hours and then Magnesium and Titanium content was determined. Upon ICP-OES analysis of catalyst 3, Mg content was found to be 13.86% and Ti content was found to be 9.19%.
[00124] Synthesis of Ziegler-Natta catalyst using Isomannide Benzoate Ester (IMBE) as internal donor (Cat 4) – using MgCl2.EtOH adduct assupport
[00125] Step 1 - MgCl2.EtOH adduct synthesis: Anhydrous MgCl2 (4.76 g) was taken from glove box in a Schlenk RBF and dry ethanol (10ml) and 50 mL of dry heptane was syringed. The reaction mixture was heated at 100 °C for 1 hour and then cool down to 70 °C. IMBE internal donor (varying concentration) was added at 70 °C temperature and again reaction temperature was increased to 100 °C and heated for 2 hours. Reaction mixture was cool down to 70 °C and 100 mL dry Decane was syringed and stirred vigorously. The ethanol was evaporated at 70 °C and then the remaining solvents (heptane + decane) was removed by cannula filtration. The solid obtained was washed with heptane (50 mL * 4) and dried under vacuum for 3 hours. The resultant MgCl2.EtOH adduct is used for step 2 for titanation.
[00126] Step 2 - TiCl4 treatment to MgCl2.EtOH adduct: The above adduct from step 1 was taken in a 3-neck RBF and TiCl4 (30ml) was added and reaction mixture was heated to 120 °C for 2 hours. The reaction mixture was cooled to 90 °C and the TiCl4 was removed by cannula filtration at 90 °C temperature. Again TiCl4 was added and the reaction mixture was heated at 120 °C for 1 hour and TiCl4 was filtered off at 90 °C. The addition and removal of TiCl4 was carried out one more time (total 3 times TiCl4 treatment). Finally, solid was washed with dry heptane (60 mL * 6) and final washing was given by dry hexane (60 mL * 1). The obtained solid catalyst was dried under vacuum for few hours and then Magnesium and Titanium content was determined.
[00127] Synthesis of Ziegler-Natta catalyst using Isomannide Acetate Ester (IMAE) as internal donor (Cat 5) – using MgCl2.EtOH adduct assupport
[00128] Step 1 - MgCl2.EtOH adduct synthesis: Anhydrous MgCl2 (4.76 g) was taken from glove box in a Schlenk RBF and dry ethanol (10ml) and 50 mL of dry heptane was syringed. The reaction mixture was heated at 100 °C for 1 hour and then cool down to 70 °C. IMBE internal donor (varying concentration) was added at 70 °C temperature and again reaction temperature was increased to 100 °C and heated for 2 hours. Reaction mixture was cool down to 70 °C and 100 mL dry Decane was syringed and stirred vigorously. The ethanol was evaporated at 70 °C and then the remaining solvents (heptane + decane) was removed by cannula filtration. The solid obtained was washed with heptane (50 mL * 4) and dried under vacuum for 3 hours. The resultant MgCl2.EtOH adduct is used for step 2 for titanation.
[00129] Step 2 - TiCl4 treatment to MgCl2.EtOH adduct: The above adduct from step 1 was taken in a 3-neck RBF and TiCl4 (30ml) was added and reaction mixture was heated to 120 °C for 2 hours. The reaction mixture was cooled to 90 °C and the TiCl4 was removed by cannula filtration at 90 °C temperature. Again TiCl4 was added and the reaction mixture was heated at 120 °C for 1 hour and TiCl4 was filtered off at 90 °C. The addition and removal of TiCl4 was carried out one more time (total 3 times TiCl4 treatment). Finally, solid was washed with dry heptane (60 mL * 6) and final washing was given by dry hexane (60 mL * 1). The obtained solid catalyst was dried under vacuum for few hours and then Magnesium and Titanium content was determined.
[00130] COMPARATIVE EXAMPLE - Synthesis of Ziegler-Natta catalyst using Di-isobutylphthalate (DIBP) as internal donor (Cat6)– using MgCl2 as support:

[00131] Step1: Anhydrous MgCl2 (2.5 g) was taken from glove box in a Schlenk RBF and dry chlorobenzene (~58 mL) was syringed under nitrogen atmosphere. TiCl4 (57.59 mL) was added dropwise using pressure equalizing dropping funnel under nitrogen. Reaction mixture was heated to 130°C for 60 minutes and cool down to the 60-70°C. At this temperature, DIBP (1.40 mL) was added and reaction mixture was heated at 130°C for 60 minutes. Reaction mixture was cool down to 60°C and the solvent was removed using cannula under nitrogen.
[00132] Step 2: Addition of chlorobenzene and TiCl4 was carried out followed by the heating of the reaction mixture at 130°C for 60 minutes. Again reaction mixture was cool down to 60°C and solvent was removed by cannula under nitrogen atmosphere.
[00133] Step 3: Step 2 was repeated again to obtain the solid catalyst.
[00134] Step4: Solid catalyst obtained was washed using dry hexane (100 ml * 3) and dried under vacuum. Catalyst was stored inside the glove box for further use. Yield of the catalyst was 1.8 g (72 %). FTIR spectra of catalyst 6 (Cat 6) is provided at FIG. 7. Upon ICP-OES analysis of catalyst 1, Mg content was found to be 23% and Ti content was found to be 2.1%.
[00135] Synthesis of Ziegler-Natta catalyst using Isosorbide Benzoate Ester (ISBE) as internal donor (Cat7) – using MgCl2 as support:

[00136] Step 1: Anhydrous MgCl2 (2.5 g) was taken from glove box in a Schlenk RBF and dry chlorobenzene (~58 mL) was syringed under nitrogen atmosphere. TiCl4 (57.59 mL) was added dropwise using pressure equalizing dropping funnel under nitrogen. Reaction mixture was heated to 130°C for 60 minutes and cool down to the 60-70°C. At this temperature, Isosorbide Benzoate Ester (ISBE) (1.8 g) was added and reaction mixture was heated at 130°C for 60 minutes. Reaction mixture was cool down to 60°C and the solvent was removed using cannula under nitrogen.
[00137] Step 2: Further, addition of chlorobenzene and TiCl4 was carried out followed by the heating of reaction mixture at 130°C for 60 minutes. Again reaction mixture was cool down to 60°C and solvent was removed by cannula under nitrogen atmosphere.
[00138] Step 3: Step 2 was repeated again to obtain the solid catalyst.
[00139] Step 4: Solid catalyst obtained from step 3 was washed using dry hexane (100 mL * 3) and dried under vacuum. Catalyst was stored inside the glove box for further use. Yield was found to be 2 g (80 %). FTIR spectra of catalyst 7 (Cat 7) is provided at FIG. 8. Upon ICP-OES analysis of catalyst 7, Mg content was found to be 1.4% and Ti content was found to be 1.6%.
PROPYLENE AND ETHYLENE POLYMERIZATION
[00140] Polymerization reactions were performed in high pressure Polyclave reactor. Before polymerization, reactor was kept for baking under vacuum at 100°C for 1 hour. Reactor was then cool down to 30°C and then kept under nitrogen flow (1 bar). Simultaneously, Ziegler-Natta catalyst (prepared in examples above i.e. catalysts 1-7) was weighed inside the glove box. Freshly distilled hexane (400 mL + 100 mL) was taken into two addition vessels under nitrogen. Appropriate amount of co-catalyst was transferred to the solvent containing vessels (half co-catalyst in 400 mL solvent vessel and half co-catalyst in 100 mL solvent vessel). Then external donor (if required) was added to the 100 mL solvent vessel. Then the catalyst was also added to 100 mL solvent vessel and stirred for 5 minutes. Simultaneously, reactor was kept under positive propylene flow and the mixture from 100 mL vessel with catalyst, co-catalyst and external donor was transferred to the high pressure reactor under positive propylene flow. After that the 400 mL of solvent was transferred to the reactor and immediately stirring and heating of the reactor was turned on. Polymerization reactions were run for 2 hours at 80°C temperature with 2.5 bar of propylene pressure. After that, the reactor was vented-off and the polymerization reaction was quenched by acidic methanol. The obtained solid precipitate was filtered-off and dried at 60°C inside the hot air oven. Table 1 below provide details of the polymerization reactions.
Table 1: Details of the propylene polymerization reactions/experiments
Exp. No. Catalyst Co-catalyst Al:Ti External Donor Al:Si Polymerization Process Conditions Activity (g PP/g catalyst)
Solvent (mL) Pressure (bar) H2 (bar) Temp (oC) Time (hr) RPM
1 Cat-01 TEAL 10% 100 CHMDMS 2.5 500 3.5 0.35 75 3 600 110
2 Cat-02 TEAL 10% 100 CHMDMS 2.5 500 4.6 0.51 75 2 600 227
3 Cat-02 TEAL 10% 100 CHMDMS 2.5 500 5.2 _ 75 2 600 234
4 Cat-02 TEAL 10% 100 CHMDMS 4 500 6 _ 75 2 600 552
5 Cat-02 TEAL 10% 100 CHMDMS 2.5 500 5.2 - 75 1 600 283
6 Cat-02 TEAL 10% 200 CHMDMS 5 500 5.2 - 75 1 600 273
7 Cat-02 TEAL 10% 500 CHMDMS 12.5 500 5.2 - 75 2 600 293
8 Cat-02 TEAL 10% 100 CHMDMS 2.5 500 5.2 0.1 75 2 600 337
9 Cat-02 TEAL 10% 100 CHMDMS 2.5 500 5.2 0.2 75 2 600 391
10 Cat-02 TEAL 10% 250 CHMDMS 40 500 5.2 0.2 70 2 600 914
TEAL: triethylaluminum; CHMDMS: cyclohexyl methyl dimethoxysilane
[00141] Data pertaining to DSC analysis of the resultant polypropylene polymers is provided in Table 2 below:
Table 2: Characteristics of the resultant polypropylene polymers – DSC analysis
Exp. no. Tm(°C) ?Hm (J/g) Tc (°C) ?Hc (J/g) %Xc
1 161.2 126.46 118.89 124.35 61.10
2 163.12 90.793 114.68 99.577 43.86
3 162.27 67.486 110.6 81.675 23.00
4 160.91 66.437 109.43 79.985 32.09
5 160.57 68.086 111.00 76.072 32.89
6 160.11 58.273 105.92 72.376 28.15
7 159.27 49.849 110.79 61.220 24.09
8 159.74 72.883 110.72 91.844 35.20
9 159.72 61.662 111.38 86.229 29.78
10 158.23 78.412 113.87 88.868 37.88

[00142] SEM images of the resultant polypropylene, according to Exp. 7-9, are provided at FIG. 9A-9C, respectively. Powder XRD data pertaining to the resultant polypropylene, according to Exp. 5-8, are provided at FIG. 10A-10D, respectively.
[00143] Similarly, ethylene polymerization was also carried out, details wherefore is summarized in Table 3 below.
Table 3: Details of ethylene polymerization reactions/experiments
Exp. No. Catalyst Co-catalyst Al:Ti Polymerization Process Conditions Activity (g PP/g catalyst)
Solvent (mL) Pressure
(bar) H2
(bar) Temp (oC) Time (hr) RPM
1a Cat-02 TEAL 10% 10 500 3 - 50 2 600 563
2a Cat-02 TEAL 10% 10 500 3 _ 60 2 600 1082
3a Cat-02 TEAL 10% 10 500 3 _ 70 2 600 783
4a Cat-02 TEAL 10% 10 500 3 - 70 1 600 746
5a Cat-02 TEAL 10% 100 500 3.2 0.4 70 1 600 807
6a Cat-02 TEAL 10% 50 500 4 0.4 70 1.5 600 768
7a Cat-02 TEAL 10% 50 500 4 1 70 1.5 600 1047
8a* Cat-02 TEAL 10% 20 500 5 - 70 1 600 1896
*catalyst used 50mg
[00144] Data pertaining to DSC analysis of the resultant polyethylene polymers is provided in Table 4 below:
Table 4: Characteristics of the resultant polyethylene polymer – DSC analysis
Exp. no. Tm(°C) ?Hm (J/g) Tc (°C) ?Hc (J/g) %Xc
1a 134.26 163.20 114.76 160.12 55.70
2a 135.51 155.27 116.04 148.49 53.00
3a 135.56 142.22 115.58 135.62 48.53
4a 136.48 155.86 116.86 154.90 53.19
5a 135.09 177.09 115.54 174.64 60.44
6a 135.48 157.63 115.37 160.87 53.80
7a 135.91 171.97 114.85 166.37 58.70
8a 135.52 120.88 115.89 122.03 41.25

[00145] SEM images of the resultant polyethylene (corresponding to Exp. nos. 2a, 4a and 8a) are provided at FIGS. 11A-C. Powder XRD data pertaining to the resultant polyethylene (corresponding to Exp. nos. 1a, 2a and 3a) is also provided at FIGS. 12A-C.
[00146] From the above experiments, it could be concluded that the synthesized catalyst using biobased internal electron donors are able to produce polyolefin such as polypropylene and polyethylene. The polypropylene obtained herein showed melting temperature in the range of 154°C to 162 °C, which is in good match with the polypropylene produced by phthalate based catalyst. Similarly, for polyethylene, the melting temperature was in the range of 134°C to 136 °C which is well comparable with the polyethylene produced by conventional Ziegler-Natta catalysts.

ADVANTAGES
[00147] The present disclosure provides internal electron donors that overcome one or more shortcomings of the conventional internal electron donors in Ziegler-Natta catalysts.
[00148] The present disclosure provides a method for production of internal electron donors.
[00149] The present disclosure provides Ziegler-Natta catalysts that overcome one or more shortcomings of the conventional Ziegler-Natta catalysts.
[00150] The present disclosure provides Ziegler-Natta catalyst that is non-toxic, environment friendly and commercially viable.
[00151] The present disclosure provides a method of production of polypropylene that is non-toxic, environment friendly and commercially viable.

, Claims:1. A method for preparing a Ziegler-Natta catalyst, said method comprising at least the step of mixing a magnesium support with a transition metal halide in presence of an internal donor compound of formula I or an isomer or mixtures thereof:

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12 aryl group, and C6 to C12 heteroaryl group.
2. The method as claimed in claim 1, wherein R1 and R2 in the internal donor compound of formula I, independent of each other, are selected from methyl and phenyl.
3. The method as claimed in claim 1, wherein the magnesium support is selected from MgCl2 and an adduct MgCl2.mR3OH, wherein R3 represents linear or branched alkyl group with 1 to 12 carbon atoms, and m ranges between1 to 6.
4. The method as claimed in one or more of claims 1 to 3, wherein the step of mixing comprises:
(a) mixing MgCl2 with an alcohol of formula R3OH at a temperature ranging from 50°C to 150°C in presence of the internal donor compound of formula I or isomer or mixtures thereof to obtain an internal donor treated magnesium support, wherein R3 represents linear or branched alkyl group with 1 to 12 carbon atoms;
(b) mixing the internal donor treated magnesium support from step (a) with the transition metal halide at a temperature ranging from 50°C to 150°C to obtain the Ziegler-Natta catalyst.
5. The method as claimed in claim 4, wherein R3 in the alcohol of formula R3OH is ethyl group, and wherein the transition metal halide is titanium halide.
6. The method as claimed in one or more of claims 1 to 3, wherein the step of mixing comprises:
(a) mixing the magnesium support with the transition metal halide at a temperature ranging from 50°C to 150°C to obtain a reaction mixture; and
(b) adding the internal donor compound of formula I or the isomer or mixtures thereof to the reaction mixture of step (a) at a temperature ranging from 50°C to 150°C to obtain the Ziegler-Natta catalyst.
7. The method as claimed in any one of the claims 1-6, wherein the internal donor compound of formula I is selected from a compound having formula Ia or formula Ib:

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12aryl group, and C6 to C12 heteroaryl group.
8. The method as claimed in any one of the claims 1-7, wherein the internal donor compound is selected from:
,
, and .
9. A Ziegler-Natta catalyst, said catalyst comprising:
(a) an internal donor compound of formula I or an isomer or mixtures thereof

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12aryl group, and C6 to C12heteroaryl group;
(b) a transition metal halide; and
(c) a magnesium support.
10. The catalyst as claimed in claim 9, wherein R1 and R2 in the internal donor compound of formula I, independent of each other, are selected from methyl and phenyl.
11. The catalyst as claimed in claim 9, wherein the magnesium support is selected from MgCl2 and an adduct MgCl2.mR3OH, wherein R3 represents linear or branched alkyl group with 1 to 12 carbon atoms, and m ranges between 1 to 6.
12. The catalyst as claimed in claim 9, wherein the transition metal halide is titanium halide.
13. The catalyst as claimed in any one of the claims 9-12, wherein the internal donor compound of formula I is selected from a compound having formula Ia or formula Ib:

wherein R1 and R2, independent of each other, is selected from C1 to C8 alkyl group, C6 to C12aryl group, and C6 to C12heteroaryl group.
14. The catalyst as claimed in any one of the claims 9-13, wherein the internal donor compound is selected from:
,
, and .
15. A method for preparing polyolefin obtained from olefin polymerization in presence of the Ziegler-Natta catalyst obtained from the method as claimed in one or more of claims 1 to 8 or the Ziegler-Natta catalyst as claimed in one or more of claims 9 to 14.
16. A polyolefin obtained from the method as claimed in claim 15.