CLIAMS:1. A composition for polymerization and pigmentation of a polymer, said composition containing a catalyst dye slurry comprising:

o a Ziegler-Natta catalyst, wherein said Ziegler-Natta catalyst comprises a pro-catalyst component, and a co-catalyst component, wherein the molar ratio of said pro-catalyst and said co-catalyst component ranges from 1:10 to 1:18; and
o an additive, wherein said additive is a dye/pigment selected form the group consisting of phthalocyanine blue, phthalocyanine green, methyl violet, iso-indoline, perylene-3,4,9,10-tetracarboxylic di-anhydride, Bismarck Brown Y, azo compound, and mixture of azo compounds.

2. A process for preparing a uniformly colored polymer, said process comprising the following steps:

A. providing a Ziegler-Natta catalyst comprising:
• a pro-catalyst component; and
• a co-catalyst component,
wherein the molar ratio of said pro-catalyst and said co-catalyst component ranges from 1:10 to 1:18;
• adding said Ziegler-Natta catalyst to a solvent containing a mixture of paraffins and aromatics to obtain a homogenized catalyst mixture.
B.
• introducing a pre-determined amount of additive and a pre-determined volume of toluene in an ultrasonic bath to obtain a slurry; and
• sonicating said slurry in said ultrasonic bath for a time period ranging from 5 minutes to 10 minutes to obtain a homogenized dye mixture.
C.
• mixing said homogenized catalyst mixture and said homogenized dye mixture to obtain a catalyst dye slurry; and
• adding said catalyst dye slurry to a monomer and polymerizing the monomer in a temperature ranging from 70 oC to 75 oC and at a pressure ranging from 2 bar to 2.5 bar for a time period ranging from 1 hour to 3 hours while stirring to obtain said uniformly colored polymer followed by filtering, washing, and drying.

3. The process as claimed in claim 2, wherein said additive is a dye/pigment selected form the group consisting of phthalocyanine blue, phthalocyanine green, methyl violet, iso-indoline, perylene-3,4,9,10-tetracarboxylic di-anhydride, Bismarck Brown Y, azo compound, and mixture of azo compound. ,TagSPECI:FIELD OF DISCLOSURE
The present disclosure relates to a composition for polymerization and pigmentation of a polymer.
BACKGROUND
Generally, polymers of olefin monomers with molecular weight higher than 1×106 g/mol are termed as “Ultrahigh Molecular Weight (UHMW)” poly-olefins. The presence of long and linear polymeric chains as longer chains serve to transfer load more effectively to the polymer backbone by strengthening intermolecular interactions. Therefore, Ultrahigh Molecular Weight Polyethylene (UHMWPE) to demonstrate excellent toughness and high impact strength.
Ultrahigh Molecular Weight Polyethylene (UHMWPE) has unique properties like increased intrinsic viscosity, enhanced porosity, enhanced crystallinity, lower to moderate bulk density, and reduced chain entanglement. Conventionally, Ultrahigh Molecular Weight Polyethylene is prepared by polymerization of ethylene catalyzed by Ziegler Natta catalyst systems in a mixed flow reactor. It can also be made using metallocene or non-metallocene type catalyst compositions. These metallocene or non-metallocene type catalyst are also termed as single site catalysts. The homogeneous catalysts used for polymerization reactions are mainly composed of transition metal complexes, wherein the transition metals used are Titanium, Zirconium, Hafnium and the like. The activation of homogeneous single site catalysts is costly as they require larger quantity of co-catalyst for activation. Use of large quantity of co-catalyst results in less kinetic control and consequently reactor fouling by generation and deposition of polymer lumps on the reactor unit walls and stirrer shaft/paddle assembly. The use of homogeneous catalyst composition, therefore, leads to increased polymerization cost.
Heterogeneous Ziegler-Natta catalyst compositions comprising titanium and magnesium as a pro-catalyst and organoaluminium as a co-catalyst are known catalyst compositions for polymerization reaction. Modification of the Ziegler-Natta catalyst compositions is known in order to obtain enhanced properties in polymers, desired for specific applications.
The activity of Ziegler-Natta catalyst compositions largely depends on the stability of titanium (Ti+3)/ (Ti+2) ion geometry, which is responsible for the growth of a polymer chain during the polymerization process. To improve the stability of titanium (Ti+3)/ (Ti+2) ion in the catalyst composition, electron donors are preferably added before the activation of the pro-catalyst component. A variety of compounds have therefore been explored as internal and external electron donors for the modification of heterogeneous Ziegler-Natta catalyst compositions.
Conventionally, monomers are polymerized in the presence of the Ziegler-Natta catalyst to obtain a polymer. The polymer is then blended with a dye/pigment before or during extrusion of the polymer to obtain a colored polymer. However, the conventional method requires an additional step of blending the polymer with the dye/pigment.
Hence, there is a need to obviate the drawbacks associated with the conventional method/s.
OBJECTS
Some of the objects of the present disclosure are described herein below:
It is an object of the present disclosure to ameliorate one or more problems associated with the conventional polymerization reaction or at least provide a useful alternative.
Another object of the present disclosure is to provide a composition for polymerization and pigmentation of a polymer.
Yet another object of the present disclosure is to provide a process for preparing a uniformly colored polymer having properties like ultra-high molecular weight, increased intrinsic viscosity, enhanced porosity, enhanced crystallinity, lower to moderate bulk density, and reduced chain entanglement.
A further object of the present disclosure is to provide a simple and cost-effective polymerization process.
SUMMARY
The present disclosure provides a composition for polymerization and pigmentation of a polymer. The composition containing a catalyst dye slurry comprising a Ziegler-Natta catalyst, wherein the Ziegler-Natta catalyst comprises a pro-catalyst component, a co-catalyst component, and an additive, wherein the additive is a dye/pigment selected form the group consisting of phthalocyanine blue, phthalocyanine green, methyl violet, iso-indoline, perylene-3,4,9,10-tetracarboxylic di-anhydride, Bismarck Brown Y, azo compound, and mixture of azo compounds.
The molar ratio of the pro-catalyst component and the co-catalyst component ranges from 1:10 to 1:18.
DETAILED DESCRIPTION
The present disclosure provides a composition for polymerization and pigmentation of a polymer. The present disclosure also provides a process for preparing a uniformly colored polymer. The uniformly colored polymers prepared by polymerization have unique properties like ultrahigh molecular weight, enhanced crystallinity, porosity, and flaky morphology.
In a first aspect, the present disclosure provides a composition for polymerization and pigmentation of a polymer. The composition containing a catalyst dye slurry comprising a Ziegler-Natta catalyst, wherein the Ziegler-Natta catalyst comprises a pro-catalyst component, and a co-catalyst component, and an additive.
In accordance with the present disclosure, the molar ratio of the pro-catalyst component and the co-catalyst component ranges from 1:10 to 1:18.

The pro-catalyst component comprises a reaction product of a magnesium containing compound and a titanium containing compound, and the co-catalyst component comprise at least one organoaluminium compound.
Typically, the magnesium containing compound is at least one compound selected from the group consisting of magnesium halides, magnesium alkoxides, magnesium aryloxides, magnesium oxyhalides and magnesium salts of inorganic acids.
Typically, the titanium containing compound is at least one compound selected from the group consisting of titanium halides, titanium alkoxides, titanium aryloxide, titanium oxides and titanium halo oxides.
The co-catalyst component is at least one selected from the group consisting of aluminum alkyls like triethyl aluminum (TEAL), triisobutyl aluminum (TIBAL), triisoprenyl aluminum (TIPRA), tri-n-octyl aluminum (TNOAL) and their homologues.
Further, the additive is a dye/pigment selected from the group consisting of phthalocyanine blue, phthalocyanine green, methyl violet, iso-indoline, perylene-3,4,9,10-tetracarboxylic di-anhydride, Bismarck Brown Y, azo compound, and mixture of azo compounds.
In a second aspect, the present disclosure provides a process for preparing a uniformly colored polymer. The process comprises the following steps:
In the first step, a Ziegler-Natta catalyst is provided which comprises:
• a pro-catalyst component; and
• a co-catalyst component.
In accordance with the present disclosure, the molar ratio of the pro-catalyst and the co-catalyst component ranges from 1:10 to 1:18.
In the second step, a homogenized catalyst mixture is obtained by adding the Ziegler-Natta catalyst to a solvent containing a mixture of paraffins and aromatics.
In accordance with one embodiment of the present disclosure, the solvent comprises a mixture of 85% paraffins (C9 to C11) and 15% aromatics.
Separately, a slurry is obtained by introducing a pre-determined amount of additive and a pre-determined volume of toluene in an ultrasonic bath.
In a following step, a homogenized dye mixture is obtained by sonicating the slurry in the ultrasonic bath for a time period ranging from 5 minutes to 10 minutes.
A catalyst dye slurry is then obtained by mixing the homogenized catalyst mixture and the homogenized dye mixture.
Further, the catalyst dye slurry is added to a monomer and the monomer is polymerized in a temperature ranging from 70 oC to 75 oC and at a pressure ranging from 2 bar to 2.5 bar for a time period ranging from 1 hour to 3 hours while stirring to obtain the uniformly colored polymer followed by filtering, washing, and drying.
Typically, the co-catalyst component is at least one selected from the group consisting of aluminum alkyls like triethyl aluminum (TEAL), triisobutyl aluminum (TIBAL), triisoprenyl aluminum (TIPRA), tri-n-octyl aluminum (TNOAL) and their other homologues.
Example of suitable dyes/pigments include phthalocyanine blue, phthalocyanine green, methyl violet, iso-indoline, perylene-3,4,9,10-tetracarboxylic di-anhydride, Bismarck Brown Y, azo compound, and mixture of azo compounds.
The colored ethylene polymer having ultrahigh molecular weight is prepared from the process as illustrated in the second aspect of the present disclosure. It is observed that the dyes or pigments used as additives were homogeneously dispersed in the polymer. Additionally, the colored polymer obtained from the above described process has unique properties like ultrahigh molecular weight, increased intrinsic viscosity, enhanced porosity, enhanced crystallinity, lower to moderate bulk density, and reduced chain entanglement.
Additives have tendency to donate electrons and interact with metal center of the Ziegler-Natta catalyst and stabilize its oxidation state. The Dye/pigment such as Phthalocyanine blue of the present disclosure favorably interacts with the metal center of the Ziegler-Natta catalyst and bonds with the metal center of the Ziegler-Natta catalyst to modify the Ziegler-Natta catalyst. It is observed that, during the polymerization reaction, the polymer starts growing around such modified Ziegler-Natta catalyst metal center, enabling the uniform dispersion of the colored dyes or pigments in the growing polymer chain that result in formation of the colored polymer.
TECHNICAL ADVANCEMENT
The present disclosure relates to a process for preparing a colored polymer in presence of a modified heterogeneous Ziegler-Natta catalyst composition, said process has several technical advancements:
• an additive like a dye/pigment modify the properties of a Ziegler-Natta catalyst;
• a composition comprising a Ziegler-Natta catalyst and a dye/pigment is capable of formation of a uniformly colored polymer;
• a process for preparing a uniformly colored polymer as disclosed in the present disclosure is simple, and cost-effective.
Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, 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.
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 invention to achieve one or more of the desired objects or results. While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Variations or modifications to the formulation of this invention, within the scope of the invention, may occur to those skilled in the art upon reviewing the disclosure herein. Such variations or modifications are well within the spirit of this invention.
The numerical values given for various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the invention unless there is a statement in the specification to the contrary