Description:TECHNICAL FIELD
The present disclosure is in the field of organic polymers. In particular, the present disclosure relates to a process of preparing high reactive polyisobutylene (HR-PIB) having at least 60 mol% exo-olefin end groups. More particularly, the process comprises polymerizing C4 hydrocarbon mixture comprising isobutylene in the presence of a catalyst complex.

BACKGROUND OF THE DISCLOSURE
Polyisobutylene (PIB) is a gas-impermeable synthetic rubber or elastomer having the linear formula [CH2C(CH3)2]n. It is a polymer of isobutylene that is colourless to light yellow, elastic rubbery, semi-solid or viscous substance and used globally to produce lubricants, adhesives, sealants, fuel additives, cling-film, and chewing gum. The commercially available PIBs can be divided into three main groups depending upon their molecular weight (Mn): (i) low-molecular weight polymers (Mn < 5000 g mol-1), (ii) medium- (Mn > 10,000–100,000 g mol-1), and (iii) high- (Mn > 100,000 g mol-1). The low-molecular weight PIBs with high content of the vinylidene/olefin (exo) end groups and narrow molecular weight distribution are called high reactive polyisobutylene (HR-PIB), represent the most important industrial class of isobutylene polymers because of their use as a raw material for manufacturing of lubricants and fuel/gasoline additives. Generally, PIBs with large proportion of olefin (exo) end groups more than 60 mol%, preferably more than 75 mol%, are normally referred to as high reactive polyisobutylene (HR-PIB).

HR-PIBs having high levels of terminal olefinic groups are of great commercial importance as they readily undergo chemical reactions. A high proportion of exo-olefin end groups are favoured to produce the additives since they have high reactivity in chemical modifications. For instance, mainly the terminal olefin groups which react with maleic anhydride in the adduct formation (additive making), whereas the double bonds located further towards the interior of the macromolecules do not react, or react to a distinctly smaller extent, depending on their position in the macromolecule, without the addition of halogens. Thus, the content of terminal olefin groups in the molecule is the most important criterion of quality polyisobutylene type.

The widely used traditional process to prepare HR-PIB is based on boron trifluoride (BF3) catalyst system. This process is performed at low temperatures, for e.g., below -30oC. The requirement of low temperatures and highly pure isobutylene monomer feed makes the process more expensive/inefficient.

Additionally, HR-PIBs are also produced by cationic polymerization of isobutylene initiated by Lewis acid-based system at temperatures below 0°C. However, halogenated (chlorinated) solvents are used in this polymerization process/reaction, which is expensive and hazardous, and also making this process difficult to handle.

Hence, there is a need for an improved method of polymerization of isobutylenes to obtain HR-PIB polymers without using toxic and expensive reagents as well as overcoming usage of chlorinated solvents employed in the polymerization reaction. The present disclosure tries to address said need.

SUMMARY OF THE DISCLOSURE
The present disclosure relates to a simple, cost-effective, single step and process for preparation of high reactive polyisobutylene polymer that does not use chlorinated solvents during catalyst preparation and can be conducted at ambient temperatures.

More particularly, the present invention relates to a process for preparing high reactive polyisobutylene (HR-PIB) polymer having at least 60 mol% exo-olefin end groups, comprising polymerizing a C4 hydrocarbon mixture comprising isobutylene in presence of a catalyst complex, to obtain the high reactive polyisobutylene (HR-PIB);
wherein the catalyst complex is a Lewis acid-ether prepared in a non-chlorinated solvent,
and wherein the Lewis acid of said catalyst complex is employed in the polymerization reaction at an amount of about 0.1 wt.% to about 1.2 wt.% with respect to the isobutylene content of the C4 hydrocarbon mixture comprising isobutylene.

In an aspect of the present disclosure, the catalyst complex is a Lewis acid-ether complex.

In some embodiments, the catalyst complex is Lewis acid-ether complex selected from aluminum chloride (AlCl3)-diisopropyl ether (C6H14O) and aluminum chloride (AlCl3)-dibutyl ether (C6H18O).

In some embodiments, the catalyst complex is a Lewis acid-ether prepared in a non-chlorinated solvent.

In some embodiments, the non-chlorinated solvent is a non-polar solvent, preferably toluene.

In some embodiments, the catalyst complex prepared in the non-chlorinated solvent is aluminum chloride (AlCl3)-diisopropyl ether (C6H14O) in toluene, or aluminum chloride (AlCl3)-dibutyl ether (C6H18O) in toluene.

In some embodiments, the C4 hydrocarbon mixture comprising isobutylene is C4 raffinate feed comprising about 10% to 90% isobutylene.

In some embodiments, the polymerization reaction is carried out at a temperature of about 5oC to about 15oC, including all values and ranges therebetween.

In some embodiments, the polymerization reaction is carried out for a time period of about 1 hour to about 5 hours, including all values and ranges therebetween.

In some embodiments, the polymerization is carried out at a temperature of about 5oC to about 15oC and for a time period of about 1 hour to about 5 hours.

In some embodiments, the process comprises polymerizing the C4 raffinate feed comprising about 10% to 90% isobutylene in the presence of aluminum chloride-diisopropyl ether catalyst complex,
wherein the aluminum chloride-diisopropyl ether is prepared in toluene,
wherein the aluminum chloride of the aluminum chloride-diisopropyl ether catalyst complex is employed at an amount of about 0.4 wt.% with respect to the isobutylene content of the C4 raffinate feed, and
wherein the obtained high reactive polyisobutylene (HR-PIB) has at least 80 mol% exo-olefin end groups.

In another aspect, the present disclosure further relates to high reactive polyisobutylene (HR-PIB) having at least 60 mol% exo-olefin end groups wherein the high reactive polyisobutylene (HR-PIB) has an average molecular weight of about 500 Dalton to about 5000 Dalton.

BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES
Figure 1 illustrates the 1H NMR spectrum of HR-PIB using aluminum chloride-diisopropyl etherate catalyst complex.

Figure 2 illustrates the Gas Phase Chromatography (GPC) traces and corresponding Mn, Mw/Mn, and exo-olefin content of the HR-PIB of the present disclosure.

DETAILED DESCRIPTION OF THE DISCLOSURE
With respect to the use of substantially any plural and/or singular terms herein (such as “a,” “an” and “the”), those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity. The various singular/plural permutations may be expressly set forth herein for sake of clarity. The suffix “(s)” at the end of any term in the present disclosure envisages in scope both the singular and plural forms of said term.

The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results. As such, the terms “a” (or “an”), “one or more”, and “at least one” can be used interchangeably herein.

Throughout this specification, the word “comprise”, or variations such as “comprises” or “comprising” or “containing” or “has” or “having” wherever used, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers, or steps, but not the exclusion of any other element, integer or step, or group of elements, integers, or steps.

Throughout this specification, the term ‘combination thereof’ or ‘combinations thereof’ or ‘any combination thereof’ or ‘any combinations thereof’ are used interchangeably and are intended to have the same meaning, as regularly known in the field of patents disclosures.

The terms “about” or “approximately” as used herein when referring to a measurable value such as a parameter, an amount, a temporal duration, and the like, are meant to encompass variations of and from the specified value, such as variations of +/- 10% or less, +/- 5% or less, +/-1% or less, and +/-0.1% or less of and from the specified value, insofar such variations are appropriate to perform in the disclosed invention. It is to be understood that the value to which the modifier “about” or “approximately” refers is itself also specifically, and preferably, disclosed.

As used herein, the term “comprising” when placed before the recitation of steps in a method means that the method encompasses one or more steps that are additional to those expressly recited, and that the additional one or more steps may be performed before, between, and/or after the recited steps. For example, a method comprising steps a, b, and c encompasses a method of steps a, b, x, and c, a method of steps a, b, c, and x, as well as a method of steps x, a, b, and c. Furthermore, the term “comprising” when placed before the recitation of steps in a method does not (although it may) require sequential performance of the listed steps, unless the content clearly dictates otherwise. For example, a method comprising steps a, b, and c encompasses, for example, a method of performing steps in the order of steps a, c, and b, the order of steps c, b, and a, and the order of steps c, a, and b, etc.

As used herein, the term ‘high reactive polyisobutylene’ or ‘HR-PIB’ refers to polyisobutylenes having average molecular weight of 500-5000 Dalton and a high content of terminal olefin groups, preferably, more than 60 mol %.

As used herein, the phrase ‘exo-olefin’ refers to terminal olefin groups, such as methyl vinylidene that readily undergo chemical reactions. In an embodiment of the present disclosure, exo-olefin group is preferably -CH2-C(CH3)=CH2.

As used herein, the phrase ‘C4 raffinate’ or ‘C4 raffinate feed’ or ‘C4 raffinate feedstock’ refers to the remaining mixture following the extraction of 1,3-butadiene from crude C4 hydrocarbon. It is a mixture of C4 hydrocarbons and is a colourless gas with a gasoline-like odour.

As used herein, the phrase ‘MW’ refers to weight average or weight average molecular weight. It is the weighted average of the polymeric chain molecular weights.

As used herein, the phrase ‘Mn’ refers to number average molecular weight of the polymer.

As used herein, the phrase ‘MW/Mn’ refers to polydispersity and is used for describing the distribution width. It defines the broadness of short and long-chain distribution of polymer chains.

The present disclosure is in relation to production of high reactive polyisobutylene (HR-PIB).

An objective of the present disclosure is to develop a simple, cost-effective, single step process for preparation of high reactive polyisobutylene polymer.

Another objective of the present disclosure is to develop a polymerization process which does not use any externally added solvent during the polymerization reaction to prepare high reactive polyisobutylene.

Another objective of the present disclosure is to develop a solvent free liquid phase polymerization process for preparation of high reactive polyisobutylene.

Yet another objective of the present disclosure is to develop a process for preparation of high reactive polyisobutylene that does not use chlorinated solvents for catalyst preparation.

Still another objective of the present disclosure is to develop a process for preparation of high reactive polyisobutylene that can be conducted at ambient temperatures.

Another objective of the present disclosure is to avoid the use of pure isobutylene and employ alternative monomer source for polymerization reaction.

Still another objective of the present disclosure is to employ a low amount of catalyst in the process of preparing high reactive polyisobutylene.

To achieve the aforesaid objectives, the present disclosure provides a process for preparing high reactive polyisobutylene (HR-PIB) polymer having at least 60 mol% exo-olefin end groups.

The present disclosure particularly relates to a process for preparing high reactive polyisobutylene (HR-PIB) polymer having at least 60 mol% exo-olefin end groups, comprising polymerizing a C4 hydrocarbon mixture comprising isobutylene in presence of a catalyst complex, to obtain the high reactive polyisobutylene (HR-PIB);
wherein the catalyst complex is a Lewis acid-ether prepared in a non-chlorinated solvent,
and wherein the Lewis acid of said catalyst complex is employed in the polymerization reaction at an amount of about 0.1 wt.% to about 1.2 wt.% with respect to the isobutylene content of the C4 hydrocarbon mixture comprising isobutylene.

In an aspect of the present disclosure, the catalyst complex is a Lewis acid-ether complex.

In some embodiments, the Lewis acid in the catalyst complex is a Group 13 element containing compound.

In some embodiments, the Lewis acid in the catalyst complex is a Group 13 element containing compound selected from a group comprising aluminum chloride (AlCl3), boron fluoride (BF3), gallium chloride (GaCl3), iron chloride (FeCl3), nickel(II) chloride (NiCl2), zinc chloride (ZnCl2), titanium tetrachloride (TiCl4), and vanadium chloride (VCl5).

In some embodiments, the Lewis acid in the catalyst complex is aluminum chloride (AlCl3).

In some embodiments, the ether group in the catalyst complex is selected from a group comprising dibutyl ether (C6H18O), diisopropyl ether (C6H14O), tert-butyl methyl ether, tert-butyl vinyl ether, and isopropyl ether.

In some embodiments, the ether group in the catalyst complex is diisopropyl ether (C6H14O).

In some embodiments, the ether group in the catalyst complex is dibutyl ether (C6H18O).

In some embodiments, the catalyst complex is Lewis acid-ether complex selected from aluminum chloride (AlCl3)-diisopropyl ether (C6H14O) and aluminum chloride (AlCl3)-dibutyl ether (C6H18O).

In some embodiments, the catalyst complex is aluminum chloride (AlCl3)-diisopropyl ether (C6H14O).

In some embodiments, the catalyst complex is aluminum chloride (AlCl3)-dibutyl ether (C6H18O).

In some embodiments, the Lewis acid and the ether group in the catalyst complex is present in a ratio of about 1:1 or 1:0.5 or 1:1.1.

In some embodiments, the catalyst complex is a Lewis acid-ether prepared in a non-chlorinated solvent.

In some embodiments, the non-chlorinated solvent is a non-polar solvent.

In some embodiments, the non-polar solvent is selected from a group comprising toluene, hexane, cyclohexane, pentane, and n-heptane.

In some embodiments, the non-polar solvent is toluene.

In some embodiments, the catalyst complex prepared in the non-chlorinated solvent is aluminum chloride (AlCl3)-diisopropyl ether (C6H14O) in toluene, or aluminum chloride (AlCl3)-dibutyl ether (C6H18O) in toluene.

In some embodiments, the catalyst complex prepared in the non-chlorinated solvent is aluminum chloride (AlCl3)-diisopropyl ether (C6H14O) in toluene.

In some embodiments, the catalyst complex prepared in the non-chlorinated solvent is aluminum chloride (AlCl3)-dibutyl ether (C6H18O) in toluene.

In the present disclosure, no chlorinated solvents are employed in the preparation of catalyst complex. In cases where chlorinated solvent is used in catalyst preparation, the C4 stream gets contaminated with chlorinated solvents thereby limiting the use of C4 stream in other processes. Thus, there will no contamination of recycled stream (after the polymerization reaction) with chlorinated solvents.

In some embodiments, the Lewis acid of the catalyst complex of the present disclosure is employed in the polymerization reaction at an amount of about 0.1 wt.% to about 1.2 wt.% with respect to the isobutylene content of the C4 hydrocarbon mixture comprising isobutylene, including all values and ranges therebetween.

In some embodiments, the Lewis acid of the catalyst complex is employed in the polymerization reaction at an amount of about 0.1 wt.%, about 0.2 wt.%, about 0.3 wt.%, about 0.4 wt.%, about 0.5 wt.%, about 0.6 wt.%, about 0.7 wt.%, about 0.8 wt.%, about 0.9 wt.%, about 1.0 wt.%, about 1.1 wt.%, or about 1.2 wt.%.

In some embodiments, the Lewis acid of the catalyst complex is employed in the polymerization reaction at an amount of about 0.4 wt.%.

In some embodiments, the Lewis acid of the catalyst complex is employed in the polymerization reaction at an amount of about 1.2 wt.%.

In some embodiments, the C4 hydrocarbon mixture comprising isobutylene is C4 raffinate feed comprising about 10% to 90% isobutylene.

In some embodiments, the C4 raffinate feed comprises about 10 mole% to 90 mole% isobutylene, about 25 mole% to 35 mole % iso-butane, and about 15 mole % to 25 mole % 1-butene.

In some embodiments, the C4 raffinate feed comprises about 10 mole% to 90 mole% isobutylene, about 25 mole % to 35 mole % iso butanes, about 15 mole % to 25 mole % 1- butene, about 5 mole% to 10 mole% n-butane, about 10 mole% to 15 mole% trans-2 butene, about 5 mole% to 10 mole% cis-2 butene, and about 0.1 mole% to 0.3 mole% propane, about 0.05 mole% to 0.1 mole% propene, about 0.1 mole% to 0.3 mole% 1,3-butadiene, and 0.05 mole% to about 0.1 mole% propadiene and impurities such as RSH (alkyl thiols or sulfhydryl compounds) in an amount of about 0.5 ppm to about 2 ppm, acetone in an amount of about 5 ppm to about 9 ppm, ammonia in an amount of about 0.5 ppm to about 1 ppm, and moisture content in an amount of about 35 ppm to 50 ppm.

In some embodiments, the C4 raffinate feed comprises about 26.28 mole% isobutylene, about 29.85 mole % iso butane, about 18.39 mole % 1- butene, about 6.69 mole% n-butane, about 11.71 mole% trans-2 butene, about 6.55 mole% cis-2 butene, and about 0.11 mole% propane, about 0.05 mole% to 0.1 mole% propene, about 0.24 mole% 1,3-butadiene, and 0.05 mole% to about 0.1 mole% propadiene and impurities such as RSH (alkyl thiols or sulfhydryl compounds) in an amount of about 1.4 ppm, acetone in an amount of about 6.17 ppm, ammonia in an amount of about 0.82 ppm, and moisture content of about 43 ppm.

In the present disclosure, the C4 raffinate feed is directly employed in the polymerization reaction without any separation of pure isobutylene. Thus, the extra cost of processing C4 raffinate feed is eliminated.

In some embodiments, the polymerization reaction is carried out at a temperature of about 5oC to about 15oC, including all values and ranges therebetween.

In some embodiments, the polymerization reaction is carried out at a temperature of about 5oC, about 6oC, about 7oC, about 8oC, about 9oC, about 10oC, about 11oC, about 12oC, about 13oC, about 14oC, or about 15oC, including all values and ranges therebetween.

In some embodiments, the polymerization reaction is carried out at a temperature of about 5oC to about 6oC.

In some embodiments, the polymerization reaction is carried out at a temperature of about 10oC to about 15oC.

In some embodiments, the polymerization reaction is carried out at a temperature of about 15oC.

In some embodiments, the polymerization reaction is carried out for a time period of about 1 hour to about 5 hours, including all values and ranges therebetween.

In some embodiments, the polymerization reaction is carried out for a time period of about 1 hour, about 2 hours, about 3 hours, about 4 hours, or about 5 hours, including all values and ranges therebetween.

In some embodiments, the polymerization reaction is carried out for a time period of about 2 hours.

In some embodiments, the polymerization reaction is carried out for a time period of about 4 hours.

In some embodiments, the polymerization is carried out at a temperature of about 5oC to about 15oC and for a time period of about 1 hour to about 5 hours.

In some embodiments, the polymerization is carried out at a temperature of about 10oC to about 15oC and for a time period of about 4 hours.

In some embodiments, the polymerization is carried out at a temperature of about 15oC and for a time period of about 2 hours.

In some embodiments of the present disclosure, the polymerization is a solvent free liquid phase polymerization. In the present disclosure, the polymerization in the present process is conducted in the absence of solvents. Thus, the energy intensive processing step of removal of the solvent from the finalized product is avoided.

In some embodiments, at the end of polymerization the prepared high reactive polyisobutylene (HR-PIB) polymer having at least 60 mol% exo-olefin end groups are separated.

In some embodiments, at the end of polymerization the remaining/unused C4 hydrocarbon mixture is recovered and recycled. In the present disclosure, since chlorinated solvents are not employed in the preparation of catalyst complex and the polymerization is conducted in the absence of solvents, the C4 hydrocarbon mixture will not be contaminated with solvents, particularly chlorinated solvents. Accordingly, the C4 hydrocarbon mixture containing isobutylene can be easily recovered and recycled for using in other processes.

In some embodiments, the process comprises polymerizing the C4 raffinate feed comprising about 10% to 90% isobutylene in the presence of aluminum chloride-diisopropyl ether catalyst complex,
wherein the aluminum chloride-diisopropyl ether is prepared in toluene,
wherein the aluminum chloride of the aluminum chloride-diisopropyl ether catalyst complex is employed at an amount of about 0.4 wt.% with respect to the isobutylene content of the C4 raffinate feed, and
wherein the obtained high reactive polyisobutylene (HR-PIB) has at least 80 mol% exo-olefin end groups.

In some embodiments, the process comprises polymerizing the C4 raffinate feed comprising about 10% to 90% isobutylene in the presence of aluminum chloride-dibutyl ether catalyst complex,
wherein the aluminum chloride-dibutyl ether is prepared in toluene,
wherein the aluminum chloride of the aluminum chloride-dibutyl ether catalyst complex is employed at an amount of about 0.4 wt.% with respect to the isobutylene content of the C4 raffinate feed, and
wherein the obtained high reactive polyisobutylene (HR-PIB) has at least 80 mol% exo-olefin end groups.

In some embodiments, the process comprises polymerizing the C4 raffinate feed comprising about 10% to 90% isobutylene in the presence of aluminum chloride-diisopropyl ether catalyst complex,
wherein the aluminum chloride-diisopropyl ether is prepared in toluene,
wherein the aluminum chloride of the aluminum chloride-diisopropyl ether catalyst complex is employed at an amount of about 1.2 wt.% with respect to the isobutylene content of the C4 raffinate feed, and
wherein the obtained high reactive polyisobutylene (HR-PIB) has at least 60 mol% exo-olefin end groups.

In some embodiments, the process comprises polymerizing the C4 raffinate feed comprising about 10% to 90% isobutylene in the presence of aluminum chloride-dibutyl ether catalyst complex,
wherein the aluminum chloride-dibutyl ether is prepared in toluene,
wherein the aluminum chloride of the aluminum chloride-dibutyl ether catalyst complex is employed at an amount of about 1.2 wt.% with respect to the isobutylene content of the C4 raffinate feed, and
wherein the obtained high reactive polyisobutylene (HR-PIB) has at least 60 mol% exo-olefin end groups.

In some embodiments, the process comprises:
- polymerizing the C4 raffinate feed comprising about 10% to 90% isobutylene in the presence of aluminum chloride-diisopropyl ether catalyst complex at a temperature of about 5oC to about 15oC for a time period of about 1 hour to about 5 hours to obtain the high reactive polyisobutylene (HR-PIB);
wherein the aluminum chloride-diisopropyl ether catalyst complex is prepared in toluene,
wherein the aluminum chloride of the aluminum chloride-diisopropyl ether catalyst complex is employed at an amount of about 1.2 wt.% with respect to the isobutylene content of the C4 raffinate feed, and
wherein the high reactive polyisobutylene (HR-PIB) has at least 60 mol% exo-olefin end groups.

In some embodiments, the process comprises:
- polymerizing the C4 raffinate comprising about 10% to 90% isobutylene in the presence of aluminum chloride-dibutyl ether catalyst complex at a temperature of about 5oC to about 15oC for a time period of about 1 hour to about 5 hours to obtain the high reactive polyisobutylene (HR-PIB);
wherein the aluminum chloride-dibutyl ether catalyst complex is prepared in toluene,
wherein the aluminum chloride of the aluminum chloride-dibutyl ether catalyst complex is employed at an amount of about 1.2 wt.% with respect to the isobutylene content of the C4 raffinate feed, and
wherein the high reactive polyisobutylene (HR-PIB) has at least 60 mol% exo-olefin end groups.

In some embodiments, the process comprises:
- polymerizing the C4 raffinate comprising about 10% to 90% isobutylene in the presence of aluminum chloride-diisopropyl ether catalyst complex at a temperature of about 5oC to about 6oC for a time period of about 2 hours to about 2.5 hours to obtain the high reactive polyisobutylene (HR-PIB);
wherein the aluminum chloride-diisopropyl ether catalyst complex is prepared in toluene,
wherein the aluminum chloride of the aluminum chloride-diisopropyl ether catalyst complex is employed at an amount of about 1.2 wt.% with respect to the isobutylene content of the C4 raffinate feed, and
wherein the high reactive polyisobutylene (HR-PIB) has at least 60 mol% exo-olefin end groups.

In some embodiments, the process comprises:
- polymerizing the C4 raffinate comprising about 10% to 90% isobutylene in the presence of aluminum chloride-diisopropyl ether catalyst complex at a temperature of about 15oC for a time period of about 2 hours to obtain the high reactive polyisobutylene (HR-PIB);
wherein the aluminum chloride-diisopropyl ether catalyst complex is prepared in toluene,
wherein the aluminum chloride of the aluminum chloride-diisopropyl ether catalyst complex is employed at an amount of about 0.4 wt.% with respect to the isobutylene content of the C4 raffinate feed, and
wherein the high reactive polyisobutylene (HR-PIB) has at least 60 mol% exo-olefin end groups.

In some embodiments, the process comprises:
- polymerizing the C4 raffinate comprising about 10% to 90% isobutylene in the presence of aluminum chloride-diisopropyl ether catalyst complex at a temperature of about 10oC to about 15oC for a time period of about 4 hours to obtain the high reactive polyisobutylene (HR-PIB);
wherein the aluminum chloride-diisopropyl ether catalyst complex is prepared in toluene,
wherein the aluminum chloride of the aluminum chloride-diisopropyl ether catalyst complex is employed at an amount of about 0.3 wt.% with respect to the isobutylene content of the C4 raffinate feed, and
wherein the high reactive polyisobutylene (HR-PIB) has at least 60 mol% exo-olefin end groups.

In some embodiments, the process comprises:
- charging aluminum chloride (AlCl3) into a round bottom flask kept under an overhead stirrer and adding toluene or hexane or cyclohexane. The whole assembly is kept under N2 atmosphere and stirred for 10 minutes;
- slowly under stirring, diisopropyl ether or dibutyl ether is added dropwise to the reaction mixture. The reaction mixture is stirred for 1 hour at room temperature (~25 °C) till a clear pale-yellow catalyst solution is formed;
- 225 mg of the catalyst slurry (prepared above) based on 0.3% of the catalyst complex on the active monomer and low molecular weight polymer (Polyisobutylene as nucleating agent 2.0 g, 13 equivalent of catalyst) in the reactor under N2 flow is prepared;
- C4 raffinate feed (300 gm) is added at appropriate rate with agitation to start polymerization at temperature of 10°C to 15°C and the heat of polymerization was dissipated to maintain temperature. The polymerization reaction is performed for approximately 4 hours. On completion of reaction, the product mass is brought to room temperature and the unreacted material is vent by heating up to 100°C.

The present disclosure further relates to high reactive polyisobutylene (HR-PIB) having at least 60 mol% exo-olefin end groups wherein the high reactive polyisobutylene (HR-PIB) has an average molecular weight of about 500 Dalton to about 5000 Dalton.

In some embodiments, the high reactive polyisobutylene (HR-PIB) has at least 60 mol% exo-olefin end groups, including all values and ranges therebetween.

In some embodiments, the high reactive polyisobutylene (HR-PIB) has at least 60 mol%, at least 65 mol%, at least 70 mol%, at least 75 mol%, at least 80 mol%, at least 85 mol%, at least 90 mol%, or at least 95 mol% exo-olefin end groups.

In some embodiments, the high reactive polyisobutylene (HR-PIB) has at least 80 mol% exo-olefin end groups.

In some embodiments, the high reactive polyisobutylene (HR-PIB) has at least 85 mol% exo-olefin end groups.

In some embodiments, the high reactive polyisobutylene (HR-PIB) has an average molecular weight of about 500 Dalton to about 5000 Dalton, preferably about 1500 Dalton to about 2500 Dalton, including all values and ranges therebetween.

In some embodiments, the MW/Mn of the high reactive polyisobutylene (HR-PIB) ranges from about 2.5 to about 5, including all values and ranges therebetween.

In some embodiments, the MW/Mn of the high reactive polyisobutylene (HR-PIB) ranges from about 2.9 to about 3.15, including all values and ranges therebetween.

Thus, the present disclosure relates to a simple, cost-effective, energy efficient, single step polymerization process for preparing high reactive polyisobutylene (HR-PIB) with a high content of exo-olefin groups. The process of the present disclosure possesses at least the following advantages:
a) The process directly employs C4 hydrocarbon mixture (for e.g., C4 raffinate feed) without any additional processing/separation of isobutylene, thereby avoiding the need of pure isobutylene, resulting in significant reduction of cost and time, leading to improved efficiency of the polymerization process.
b) The polymerization reaction is a solvent free liquid phase polymerization. Thus, polymerization reaction per se is conducted in absence of solvents and there is no requirement of separation of solvents during downstream processing, thereby making the overall process cost and energy efficient.
c) The catalyst complex per se employed in the polymerization process is prepared in non-chlorinated solvents. Thus, the use of such catalyst complex will not result in any contamination of recycled C4 hydrocarbon mixture (for e.g., C4 raffinate stream) with chlorinated solvents.
d) Lesser quantity of catalyst complex is employed in the present process, as compared to conventional polymerization processes for HR-PIB synthesis.
e) The present process is energy efficient as it is performed at 5oC to 15oC, thereby showcasing an advantage over conventional polymerization reaction for HR-PIB synthesis which is carried out at zero and sub-zero temperatures.
f) Lastly, the C4 hydrocarbon mixture containing isobutylene except HR-PIB can be recovered and recycled as the there is no contamination of solvents, particularly chlorinated solvents.

It is to be understood that the foregoing descriptive matter is illustrative of the disclosure and not a limitation. While considerable emphasis has been placed herein on the particular features of this disclosure, it will be appreciated that various modifications can be made, and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. Those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein. Similarly, additional embodiments and features of the present disclosure will be apparent to one of ordinary skill in art based upon description provided herein.

Descriptions of well-known/conventional methods/steps and techniques are omitted so as to not unnecessarily obscure the embodiments herein. Further, the disclosure herein provides for examples illustrating the above-described embodiments, and in order to illustrate the embodiments of the present disclosure certain aspects have been employed. The examples used herein for such illustration are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the following examples should not be construed as limiting the scope of the embodiments herein.

EXAMPLES

EXAMPLE 1: Preparation of catalyst complex
The complex of aluminum chloride (AlCl3¬) with diisopropyl ether (iPr2O) was prepared under glove box in toluene solution. iPr2O was added dropwise to slurry of AlCl3 in toluene (7.5 ml) for 5 to 10 minutes. The reaction was stirred for 30 to 60 minutes till complete dissolution of aluminum chloride (AlCl3) to give a solution of complex (AlCl3OPr2) in toluene.

EXAMPLE 2: Process of synthesizing high reactive polyisobutylene (HR-PIB) polymer
Slurry of the catalyst complex as prepared in the Example 1A was taken. 300 mg based on 0.4% of aluminum chloride-diisopropyl ether catalyst complex on active monomer (isobutylene content which is 25% in feedback supplied) in the reactor under N2 flow was prepared. Thereafter, C4 raffinate feed (300 gm) was added at appropriate rate with agitation to start polymerization at temperature of 15°C and heat of polymerization was dissipated to maintain temperature. The reaction was performed for approximately 2 hours. On completion of the reaction, the product mass was brought to room temperature and the unreacted material was vent by heating up to 100°C. The result of this polymerization reaction is given below in Table 1.

Table 1. HR-PIB synthesis using catalyst system (AlCl3, diisopropyl ether & toluene)
S. No C4 raffinate (g) Isobutylene content within C4 raffinate (g) Catalyst Qty (% of AlCl3 with respect to Isobutylene content of C4 raffinate)* Reactor Temp (oC) range Pressure (Kg/cm2) Time (hrs) PIB (g) PIB (Yield) % NMR Analysis
1 300 75 0.4% 5-6 2 2 60 80 Exo- 85%
Endo -10 %
Tetra- 5 %
* Catalyst system - AlCl3 (0.300 g, 6.7 mmol) + Diisopropyl ether (0.93 ml, 6.7 mmol) + Toluene (7.5 ml)
The Table clearly shows that a high reactive polyisobutylene polymer with 85 mol% exo-olefin groups was synthesized by the present process.

EXMAPLE 3: Preparation of catalyst complex and Polymer synthesis
The following experiment was carried out in triplicate. Slurry of the catalyst complex as prepared in the Example 1A was taken. 300 mg based on 1.2% of aluminum chloride-diisopropyl ether catalyst complex on active monomer (isobutylene content which is 25% in feedback supplied) in the reactor under N2 flow was prepared. Thereafter, C4 raffinate feed (300 gm) was added at appropriate rate with agitation to start polymerization at temperature of 5°C to 6oC and heat of polymerization was dissipated to maintain temperature. The reaction was performed for approximately 2 hours. On completion of the reaction, the product mass was brought to room temperature and the unreacted material was vent by heating up to 100°C. The result of this polymerization reaction is given below in Table 2.

Table 2: HR-PIB synthesis using catalyst system (AlCl3, diisopropyl ether & toluene)
Exp No C4 raffinate (g) Isobutylene content within C4 raffinate (g) Catalyst Qty (AlCl3 with respect to % of Isobutylene content of C4 raffinate)* Reactor Temp (oC) range Pressure (Kg/cm2) Time (hrs) PIB (g) PIB (Yield) % NMR analysis
%
1 300 75 1.20% 5-6 2 2 56 75 Exo- 67.6 %
Endo -17.2 %
Tetra - 15.2 %
* Catalyst system - AlCl3 (0.900 g) + Diisopropyl ether (0.93 ml) + Toluene (7.5 ml)

Example 4: NMR analysis
The 1H NMR data of HR-PIB synthesized in Example 2 is shown in Fig. 1. This 1H NMR data was analysed and compared with standard and found all peaks are matching well with the standard (See in Fig. 1) The strong resonance signals at d 1.11 and 1.42 are assigned to the -CH3 and CH2 protons in the main chain of polyisobutylene respectively. According to literature, the PIB chain normally leads to exo- or endo- double bond end groups, i.e. -CH2-C(CH3)=CH2 (exo) or -CH2- CH=C(CH3)2 (endo). The expansion of olefinic region (inset) shows two major signals at 4.63 and 4.84 ppm for the exo-olefin end groups and show more than 80% olefin end group.

The small fraction of endo-olefin-terminated polyisobutylene and coupled polyisobutylene chains are observed at 5.15 and 4.82 ppm (as a shoulder to the downfield exo-olefin peak at 4.84 ppm), respectively. The 1NMR spectrum clearly indicates the formation of high amount of exo-olefin terminal groups (exo ~85%).

EXAMPLE 5: Gel Permeation Chromatography (GPC) analysis
The HR-PIB synthesized in Example 2 was characterized (in three different batches of HR-PIB product) though GPC. An important requirement of industry toward preparation of HR PIBs is the possibility to control the molecular weight of obtained polymers. The GPC traces and corresponding results of Mn, Mw/Mn, and exo-olefin content of the resulting PIBs are presented in Table 3 and in Fig 2.

Table 3: GPC data of HR-PIB sample
Sample no. Mn Mw PDI
1 2168 6817 3.14

The result shows that the molecular weight of the HR-PIB synthesized by the present process is in the range of commercial HR-PIB product and it can be tuned through changing temperature and concentration of catalyst.

EXAMPLE 6: Comparative analysis
The HR-PIB synthesis by the present process under Example 1 and 2 was compared with HR-PIB polymer synthesis under different process conditions/parameters as shown in Table 4 below.

Table 4: Comparative analysis of the HR-PIB polymer produced by the present process vis-à-vis the HR-PIB polymer synthesized under different process conditions/parameters
Sl. No. Catalyst composition C4 raffinate/
Isobutylene Solvent Temperature (oC) Exo content (%) Conversion (%)
1 iPr2O]/[AlCl3] Pure Isobutylene CH2Cl2 0 85-88 85-88
2 iPr2O]/[AlCl3] Pure Isobutylene CH2Cl2 20 10-72 50-80
3
(Present process) iPr2O]/[AlCl3] C4 raffinate feed -- 5-15 60-90 75-85
*iPr2O=diisoproyl ether

The results of the above Table 4 clearly demonstrate that HR-PIB prepared by the improved process of the present disclosure has high exo-olefin end groups (up to 85 mol%) and is produced without using chlorinated solvents and at near ambient temperature. On the other hand, both the comparative examples employ chlorinated solvents and use pure isobutylene giving similar or inferior results. Further, as mentioned above, use of chlorinated solvents results in contamination of downstream/recycling of C4 hydrocarbon mixture and use pure isobutylene makes the process expensive – both of which are avoided in the present process.

Reference throughout this specification to “some embodiments”, “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present disclosure. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification may not necessarily all refer to the same embodiment. It is appreciated that certain features of the disclosure, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the disclosure, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

As regards the embodiments characterized in this specification, it is intended that each embodiment be read independently as well as in combination with another embodiment. For example, in case of an embodiment 1 reciting 3 alternatives A, B and C, an embodiment 2 reciting 3 alternatives D, E and F and an embodiment 3 reciting 3 alternatives G, H and I, it is to be understood that the specification unambiguously discloses embodiments corresponding to combinations A, D, G; A, D, H; A, D, I; A, E, G; A, E, H; A, E, I; A, F, G; A, F, H; A, F, I; B, D, G; B, D, H; B, D, I; B, E, G; B, E, H; B, E, I; B, F, G; B, F, H; B, F, I; C, D, G; C, D, H; C, D, I; C, E, G; C, E, H; C, E, I; C, F, G; C, F, H; C, F, I, unless specifically mentioned otherwise.

Numerical ranges stated in the form ‘from x to y’ include the values mentioned and those values that lie within the range of the respective measurement accuracy as known to the skilled person. If several preferred numerical ranges are stated in this form, of course, all the ranges formed by a combination of the different end points are also included.

As used herein, the terms “include” (any form of “include”, such as “include”), “have” (and “have”), “comprise” etc. any form of “having”, “including” (and any form of “including” such as “including”), “containing”, “comprising” or “comprises” are inclusive and will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

Any discussion or reference of documents, acts, materials, devices, articles, and the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application. Particularly, mention of any reference, article, publication, patent, patent publication, and patent application cited herein is not, and should not be taken as, an acknowledgment or any form of suggestion that they constitute valid prior art or form part of the common general knowledge in any country in the world. , Claims:WE CLAIM:

1. A process for preparing high reactive polyisobutylene (HRPIB) polymer having at least 60 mol% exo-olefin end groups, comprising polymerizing a C4 hydrocarbon mixture comprising isobutylene in presence of a catalyst complex, to obtain the high reactive polyisobutylene (HRPIB);
wherein the catalyst complex is a Lewis acid-ether prepared in a non-chlorinated solvent,
and wherein the Lewis acid of said catalyst complex is employed in the polymerization reaction at an amount of about 0.1 wt.% to about 1.2 wt.% with respect to the isobutylene content of the C4 hydrocarbon mixture.

2. The process as claimed in claim 1, wherein the Lewis acid in the catalyst complex is a Group 13 element containing compound; and
wherein the Group 13 element containing compound is selected from a group comprising aluminum chloride (AlCl3), boron fluoride (BF3), gallium chloride (GaCl3), iron chloride (FeCl3), nickel(II) chloride (NiCl2), zinc chloride (ZnCl2), titanium tetrachloride (TiCl4), and vanadium chloride (VCl5).

3. The process as claimed in claim 1, wherein the ether group in the catalyst complex is selected from a group comprising dibutyl ether (C6H18O), diisopropyl ether (C6H14O), tert-butyl methyl ether, tert-butyl vinyl ether, and isopropyl ether.

4. The process as claimed in claim 1, wherein the non-chlorinated solvent is a non-polar solvent.

5. The process as claimed in claim 4, wherein the non-polar solvent is selected from a group comprising toluene, hexane, cyclohexane, pentane, and n-heptane.

6. The process as claimed in any of the claims 1 to 5, wherein the catalyst complex is Lewis acid-ether complex selected from aluminum chloride (AlCl3)-diisopropyl ether (C6H14O) and aluminum chloride (AlCl3)-dibutyl ether (C6H18O).

7. The process as claimed in any of the claims 1 to 6, wherein the catalyst complex is prepared in the non-chlorinated solvent which is toluene;
or wherein the catalyst complex prepared in the non-chlorinated solvent is aluminum chloride (AlCl3)-diisopropyl ether (C6H14O) in toluene, or aluminum chloride (AlCl3)-dibutyl ether (C6H18O) in toluene.

8. The process as claimed in claim 1, wherein the C4 hydrocarbon mixture comprising isobutylene is C4 raffinate feed comprising about 10% to 90% isobutylene.

9. The process as claimed in claim 8, wherein the C4 raffinate comprises about 10% to 90% isobutylene, about 25 mole % to 35 mole % iso butanes, about 15 mole % to 25 mole % 1- butene, about 5 mole% to 10 mole% n-butane, about 10 mole% to 15 mole% trans-2 butene, about 5 mole% to 10 mole% cis-2 butene, and about 0.1 mole% to 0.3 mole% propane, about 0.05 mole% to 0.1 mole% propene, about 0.1 mole% to 0.3 mole% 1,3-butadiene, and 0.05 mole% to about 0.1 mole% propadiene and impurities selected from a group comprising alkyl thiols or sulfhydryl compounds in an amount of about 0.5 ppm to about 2 ppm, acetone in an amount of about 5 ppm to about 9 ppm, ammonia in an amount of about 0.5 ppm to about 1 ppm, and moisture content in an amount of about 35 ppm to 50 ppm.

10. The process as claimed in any of the claims 1 to 9, wherein the polymerization is carried out at a temperature of about 5oC to about 15oC and for a time period of about 1 hour to about 5 hours.

11. The process as claimed in any of the claims 1 to 10, wherein the polymerization is a solvent free liquid phase polymerization.

12. The process as claimed in claim 1, wherein the prepared high reactive polyisobutylene (HRPIB) polymer is separated and the recovered C4 hydrocarbon mixture is recycled.

13. The process as claimed in any of the claims 1 to 12, comprising polymerizing the C4 raffinate feed comprising about 10% to 90% isobutylene in the presence of aluminum chloride-diisopropyl ether catalyst complex,
wherein the aluminium chloride-diisopropyl ether is prepared in toluene,
wherein the aluminum chloride of the aluminium chloride-diisopropyl ether catalyst complex is employed at an amount of about 0.4 wt.% with respect to the isobutylene content of the C4 raffinate feed, and
wherein the obtained high reactive polyisobutylene (HRPIB) has at least 80 mol% exo-olefin end groups.

14. The process as claimed in any of the claims 1 to 13, comprising polymerizing the C4 raffinate feed comprising about 10% to 90% isobutylene in the presence of aluminum chloride-dibutyl ether catalyst complex,
wherein the aluminium chloride-dibutyl ether is prepared in toluene,
wherein the aluminum chloride of the aluminium chloride-dibutyl ether catalyst complex is employed at an amount of about 0.4 wt.% with respect to the isobutylene content of the C4 raffinate feed, and
wherein the obtained high reactive polyisobutylene (HRPIB) has at least 80 mol% exo-olefin end groups.

15. The process as claimed in any of the claims 1 to 14, wherein the process comprises:
- polymerizing the C4 raffinate comprising about 10% to 90% isobutylene in the presence of aluminum chloride-diisopropyl ether catalyst complex at a temperature of about 5oC to about 15oC for a time period of about 1 hour to about 5 hours to obtain the high reactive polyisobutylene (HRPIB);
wherein the aluminum chloride-diisopropyl ether catalyst complex is prepared in toluene,
wherein the aluminum chloride of the aluminum chloride-diisopropyl ether catalyst complex is employed at an amount of about 1.2 wt.% with respect to the isobutylene content of the C4 raffinate feed, and
wherein the high reactive polyisobutylene (HRPIB) has at least 60 mol% exo-olefin end groups.

16. A high reactive polyisobutylene (HRPIB) having at least 60 mol% exo-olefin end groups prepared by the process of any of the claims 1 to 15, wherein said high reactive polyisobutylene (HRPIB) has an average molecular weight of about 500 Dalton to about 5000 Dalton.