CLIAMS:1. A polyolefin resin comprising at least one polyolefin blended with at least one modifying agent selected from the group consisting of alkoxy silane of formula Si(OR)4, alcohol based phosphate ester and phenol ethoxylated phosphate ester,
wherein,
R is linear or branched alkyl group having 1 to 5 carbon atoms; and
the amount of said modifying agent ranges from 0.5 to 10 w/w%.

2. The polyolefin resin as claimed in claim 1, wherein the polyolefin is at least one selected from the group consisting of polyethylene and polypropylene.

3. The polyolefin resin as claimed in claim 1, wherein the R is linear or branched alkyl group having 2 to 4 carbon atoms.

4. The polyolefin resin as claimed in claim 1, wherein the alcohol based phosphate ester is at least one selected from the group consisting of lauryl alcohol ethoxylate, decyl alcohol ethoxylate, tridecyl alcohol ethoxylate, cetostearyl alcohol ethoxylate, cetyl alcohol ethoxylate, stearyl alcohol ethoxylate, behenyl alcohol ethoxylate, oleyl alcohol ethoxylate, lauryl myristyl alcohol ethoxylate, lauryl stearyl alcohol ethoxylate, undecyl alcohol ethoxylate, myristyl alcohol ethoxylate and oleyl cetyl alcohol ethoxylate.

5. The polyolefin resin as claimed in claim 1, wherein the phenol ethoxylated phosphate ester is at least one selected from the group consisting of nonylphenol ethoxylate phosphate esters, styrenated phenol ethoxylate phosphate esters, octylphenol ethoxylates phosphate esters, tridecyl alcohol ethoxylate phosphate esters, decyl alcohol ethoxylate phosphate esters and lauryl alcohol ethoxylate phosphate esters.

6. The polyolefin resin as claimed in claim 1, wherein the polyolefin is dry blended with the modifying agent.

7. The polyolefin resin as claimed in claim 1, wherein the amount of said modifying agent preferably ranges from 1 to 3 w/w%. ,TagSPECI:FIELD:
The present disclosure relates to polyolefin resins having enhanced hydrophilic properties

BACKGROUND:
Polyolefins are extensively used in various applications depending on physical, chemical and biological interactions on the surface of the polyolefins. Hydrophobicity, which is one of the physical properties, of a polyolefin can be advantageous in one application and disadvantageous in others since, hydrophobic property of polyolefins restricts its use in specialty applications such as medical, filtration, fiber as reinforce material, adsorbent material and packaging. A polyolefin that exhibits hydrophobic property has low surface energy resulting in unacceptable paintability, printability, dyeability and the like, whereas low hydrophilicity results in static problems thereby restricting its use with alkaline materials.
Therefore, efforts are made to hydrophilize the surface of a polyolefin through different routes to make the polyolefin suitable for high end applications.
US patents 4710540 and 4861812 suggest a hydrophilic polyolefin resin comprising a polyolefin and alkyl amino alkoxy silane blended with maleated polypropylene as a modifying agent.
US patent 5721315 suggests a compound comprising a blend of polypropylene and the reaction product of a functionalized polypropylene and polyether amine.
US20010008696 suggests a process for preparing a hydrophilic inorganic coated film. The inorganic coating comprises a silicone resin which is obtained by hydrolyzing and polymerizing alkoxysilane.

WO2005063894 suggests a thermosetting composition and formed article having hydrophilicity and antifouling property in which silane compound selected from alkoxysilanes and condensates thereof, and a curing agent are used.
KR2009010543 suggests a silane-silicon having a hydrophilic group for providing a foam resin having flame retardant properties. The silanesilicon having a hydrophilic group is mixed with an emulsion of a polymer to obtain a flame retardant foam resin.
JP7030136 suggests a polyolefin composition containing silane coupling agent such as vinyltrimethoxysilane and vinyltris(beta-methoxyethoxy)silane; an organic peroxide and hydrophilic polymer.
The suggested processes use expensive chemicals and consume energy. Further, these processes take lot of time.
Therefore, there is a need for a simple and cost effective method for hydrophilization of polyolefin using less expensive chemicals.

OBJECTS:
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
An object of the present disclosure is to provide a polyolefin resin having enhanced hydrophilic properties.
Another object of the present disclosure is to provide a simple and cost effective process for preparing a polyolefin resin having enhanced hydrophilic properties.
Still another object of the present disclosure is to provide a process for preparing a polyolefin resin having enhanced hydrophilic properties which employs less expensive chemicals.

Still another object of the present disclosure is to provide a polyolefin resin having enhanced hydrophilic properties suitable for various high end applications such as medical, filtration, fiber, adsorbent material and packaging material.

SUMMARY:
The present invention provides a polyolefin resin comprising a polyolefin blended with at least one organic or inorganic modifying agent having hydrophilic groups such as hydroxyl, ethoxy, ester and the like. The modifying agent is capable of enhancing hydrophilic properties of the polyolefin with which it is blended. The polyolefin resin of the present disclosure can be used for various applications in medical, hygiene product, filtration membranes, absorbent materials and the like.

DETAILED DESCRIPTION:

The present disclosure relates to a polyolefin resin having enhanced hydrophilic properties. The polyolefin comprises at least one polyolefin and at least one modifying agent which modify hydrophilic property of the polyolefin. The modifying agent can be organic compound or inorganic compound having hydrophilic groups such as hydroxyl, ethoxy, ester and the like. The polyolefin resin of the present invention is useful in various applications such as medical, filtration membranes, fiber reinforce material, adsorbent material, packaging material and the like.
The polyolefin in the polyolefin resin of the present disclosure is at least one selected from the group consisting of polyethylene and polypropylene.
The modifying agent used for modifying hydrophilic property of the polyolefin is at least one selected from the group consisting of alkoxy silane, alcohol based phosphate ester and phenol ethoxylated phosphate ester.

The alkoxy silane is defined herein to mean a Si (IV) compound of the formula Si (OR)4. The functional group R in the formula is an alkyl group having from 1 to 5 carbon atoms, preferably from 2 to 4 carbon atoms. The alkyl group can be linear or branched.

Examples of alcohol base phosphate ester useful for the purpose of the present invention include but are not limited to lauryl alcohol ethoxylate, decyl alcohol ethoxylate, tridecyl alcohol ethoxylate, cetostearyl alcohol ethoxylate, cetyl alcohol ethoxylate, stearyl alcohol ethoxylate, behenyl alcohol ethoxylate, oleyl alcohol ethoxylate, lauryl myristyl alcohol ethoxylate, lauryl stearyl alcohol ethoxylate, undecyl alcohol ethoxylate, myristyl alcohol ethoxylate and oleyl cetyl alcohol ethoxylate.

Examples of phenol ethoxylated phosphate ester useful for the purpose of the present invention include but are not limited to nonylphenol ethoxylate phosphate esters, styrenated phenol ethoxylate phosphate esters, octylphenol ethoxylates phosphate esters, tridecyl alcohol ethoxylate phosphate esters, decyl alcohol ethoxylate phosphate esters and lauryl alcohol ethoxylate phosphate esters.

The modifying agent modifies the hydrophilic property of the polyolefin to permit it to adhere to other materials such as inorganic material.
To obtain acceptable hydrophilic property for specialty applications, the amount of modifying agent is varied from 0.5 to 10 w/w%, particularly from 1 to 3 w/w%.

The modifying agent is compounded with the polyolefin by blending method, particularly dry blending. Blending is performed by high shear mixing using a mechanical stirrer followed by passing through an extruder to obtain films of the polyolefin resin.

The hydrophilicity property of the films was studied by measuring contact angle, deflection and diameter of water droplet.

The present disclosure is further described in light of the following examples which are set forth for illustration purpose only and not to be construed for limiting the scope of the disclosure.
Examples
Tests
In deflection tests, the films were dipped in a mixture of organic and polar solvent. The organic solvent used herein was n-decane and polar solvent was water. The deflection of the film towards the polar solvent was observed which indicates the hydrophilic nature of the polyolefin resin films.
In microscopic observation the affinity of water towards the polyolefin resin films was evaluated by measuring the diameter of water droplet using computer assisted microscopic observation. The water droplet becomes wider on a hydrophilic surface as compared to hydrophobic surface. The results of these tests and observations are tabulated to show the increased hydrophilic property of the polyolefin resin of the present disclosure.

Example 1:
Polypropylene was blended with 1 w/w% of modifying agent in a high shear single arm mechanical stirrer followed by passing through extruder to obtain films. Films of the polypropylene resin were subjected to test methods to determine hydrophilic property of polypropylene. Results are tabulated in Table 1.

Table 1: Hydrophilicity measurement of polypropylene resin films containing 1 w/w % modifying agent

S.No. Polymer film Contact Angle
Before water washing
Contact Angle
After water washing
Deflection of film
(in mm) Diameter of water droplet using microscope
(in pxi)
1 Homo polypropylene 90° 92° 0
329 pxi
2 Polypropylene resin comprising a blend of polypropylene and tetraethoxy silane
73° 82° 3
358 pxi
3 Polypropylene resin comprising a blend of polypropylene and Nonyl phenol ethoxylate phosphate ester 59° 69° 12 436 pxi
4 Polypropylene resin comprising a blend of polypropylene and tridecyl alcohol ethoxylate phosphate ester 64° 72° 8
433 pxi

Example 2:
Polypropylene was blended with 3 w/w% of modifying agent in a high shear single arm mechanical stirrer followed by passing through extruder to obtain films. Films of the polypropylene resin were subjected to test methods to determine hydrophilic property of polypropylene. Results are tabulated in Table 2.

Table 2: Hydrophilicity measurement of polypropylene resin films containing 3 w/w % modifying agent

S.No. Polymer film Contact Angle
Before water washing
Contact Angle
After water washing
Deflection of film
(in mm) Diameter of water droplet using microscope
(in pxi)
1 Homo polypropylene 90° 92° 0 329 pxi
2 Polypropylene resin comprising a blend of polypropylene and tetraethoxy silane
69° 75° 6 409 pxi
3 Polypropylene resin comprising a blend of polypropylene and Nonyl phenol ethoxylate phosphate ester 50° 63° 20 451 pxi
4 Polypropylene resin comprising a blend of polypropylene and tridecyl alcohol ethoxylate phosphate ester 59° 69° 12 443 pxi

Example 3:
Polypropylene was blended with 3 w/w% of mixture of two modifying agents in 1:1 in a high shear single arm mechanical stirrer followed by passing through extruder to obtain films. Films of the polypropylene resin were subjected to test methods to determine hydrophilic property of polypropylene. Results are tabulated in Table 2.

Table 3: Hydrophilicity measurement of polypropylene resin films made from a polypropylene and a mixture of two modifying agents in 1:1 ratio.

S.No. Polymer film Contact Angle
Deflection of film
(in mm) Diameter of water droplet using microscope
(in pxi)
1 Homo polypropylene 90° 0
329 pxi
3 Polypropylene resin comprising a blend of polypropylene, Tetraethoxy silane and Nonyl phenol ethoxylate phosphate ester 62° 10

415 pxi
4 Polypropylene resin comprising a blend of polypropylene, Tetraethoxy silane and tridecyl alcohol ethoxylate phosphate ester 67° 13

417 pxi

From the results shown in tables 1, 2 and 3, it can be concluded that the hydrophilic property of a polyolefin is enhanced by blending a polyolefin with a suitable modifying agent.

TECHNICAL ADVANCEMENT AND ECONOMIC SIGNIFICANCE
The present disclosure provides
- a simple and direct approach for the enhancement of hydrophilic nature of polyolefin resin,
- permits a method for producing polyolefin having enhanced hydrophilic properties for number of applications, and
- cost effective method for preparation of modified polyolefin.

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 disclosure to achieve one or more of the desired objects or results.
Any discussion of documents, acts, materials, devices, articles or 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.
The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.
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. These and other modifications in the nature of the disclosure or the preferred embodiments will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.
The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, 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.