Process for the polymerization of pentabromobenzyl (meth) acrylate, the polymer obtained and uses thereof

Patent metadata

Field	Value
Publication number	US-2015259440-A1
Application number	US-201314435312-A
Country	US
Kind code	A1
Filing date	Oct 17, 2013
Priority date	Oct 17, 2012
Publication date	Sep 17, 2015
Grant date	—

Abstract

The invention provides a solution polymerization process, comprising polymerizing pentabromobenzyl acrylate or pentabromobenzyl methacrylate in a mixture of water-miscible aprotic solvent and water, in the presence of a water-soluble free radical initiator and preferably also chain length regulator. The polymers obtained and their uses as flame retardants in polypropylene, HIPS, ABS and textile products are also disclosed.

First claim

1 . A solution polymerization process comprising polymerizing a monomer of the formula

wherein R is H or methyl, in a mixture of water-miscible aprotic solvent and water, in the of presence of a free radical initiator.

2 . The process according to claim 1 , wherein the free radical initiator is water soluble.

3 . The process according to claim 1 , wherein the polymerization is carried out in the presence of a chain length regulator.

4 . The process according to claim 3 , wherein the monomer is pentabromobenzyl aerylate (R═H).

5 . The process according to claim 4 , wherein the water-miscible aprotic solvent is selected from the group consisting of glycol ethers.

6 . The process of claim 5 , wherein the solvent is selected from the group consisting of dialkyl ethers of ethylene glycol and dialkyl ethers diethylene glycol.

7 . The process according to claim 1 , wherein the initiator is a persulfate salt.

8 . The process according to claim 3 , wherein the chain length regulator is a thiol compound.

9 . The process according to claim 8 , wherein the thiol is RiSH wherein Ri an alkyl group composed of not less than 8 carbon atoms.

10 . Poly (pentabromobenzyl acrylate) having weight average molecular weight (Mw) in the range from 4,000 to 120,000 and polydispersity index of less than 10 as determined by high temperature gel permeation chromatography, wherein the glass transition temperature of the poly (pentabromobenzyl acrylate) is not more than 150° C.

11 . Poly (pentabromobenzyl acrylate) according to claim 10 , wherein the Mw is in the range from 4,000 to 90,000, the polydispersity index is between 2 and 10 and the glass transition temperature is between 20 and 150° C.

12 . Poly (pentabromobenzyl acrylate) according to claim 11 , wherein the Mw is in the range from 4,000 to 30,000 and the glass transition temperature is between 20 and 135° C.

13 . Poly (pentabromobenzyl acrylate) according to claim 11 , wherein the Mw is in the range from 30,000 to 90,000 and the glass transition temperature is between 135 and 150° C.

14 . Poly (pentabromobenzyl acrylate) according to claim 13 , wherein the Mw is in the range from 40,000 to 90,000 and the glass transition temperature is between 140 and 150° C.

15 . Poly (pentabromobenzyl acrylate) according to claim 10 , comprising chains which are terminated by an end group derived from a chain length regulator.

16 . Poly (pentabromobenzyl acrylate) according to claim 15 , wherein the end group is a thiol group —SRi, wherein Ri is a linear or branched alkyl group composed of not less than 8 carbon atoms.

17 . Poly (pentabromobenzyl acrylate) according to claim 16 , wherein the end group is —S(CH 2 ) n CH 3 with n ranging from 8 to 20.

18 . A formulation which comprises a flammable material and the poly (pentabromobenzyl acrylate) as defined in claim 10 as a flame retardant.

19 . A formulation according to claim 18 , wherein the flammable material is a polypropylene copolymer or impact modified polypropylene.

20 . A formulation according to claim 19 , which further comprises antimony trioxide, wherein the bromine content of the formulation is in the range from 7 to 10 wt % and the bromine/Sb 2 O 3 weight ratio is less than 4:1.

21 . A formulation according to claim 19 , which is a talc-free formulation, comprising poly (pentabromobenzyl acrylate) having weight average molecular weight (Mw) in the range from 4,000 to 30,000 and polydispersity index of between 2 and 10 as determined by high temperature gel permeation chromatography, wherein the glass transition temperature of the poly (pentabromobenzyl acrylate) is between 20 and 135° C. and antimony trioxide, such that the combined concentration of bromine and antimony trioxide relative to the total weight of the formulation is less than 34 wt %, with the bromine/Sb 2 O 3 weight ratio being not more than 2:1.

22 . A formulation according to claim 18 , wherein the flammable material comprises a styrene-containing polymer or copolymer.

23 . A formulation according to claim 22 , wherein the styrene-containing copolymer is selected from the group consisting of high-impact polystyrene (HIPS) and acrylonitrile butadiene styrene (ABS), wherein said formulation further comprises antimony trioxide at weight concentration of not more than 1.5 wt %.

24 . A formulation according to claim 18 , wherein the flammable material is a textile product.

25 . A formulation according to claim 24 , wherein the poly (pentabromobenzyl acrylate) has a weight average molecular weight (Mw) in the range from 30,000 to 90,000 and polydispersity index of between 2 and 10 as determined by high temperature gel permeation chromatography, wherein the glass transition temperature of the poly (pentabromobenzyl acrylate) is between 135 and 150° C.

26 . A composition comprising poly (pentabromobenzyl acrylate) according to claim 10 , an aqueous carrier and a polymer binder, and optionally one or more additives selected from the group consisting of wetting agents, dispersants and thickeners.

27 . A method for reducing the flammability of a textile product, comprising applying poly (pentabromobenzyl acrylate) of claim 13 to said product by padding or coating a surface of said product.

Assignees

• Bromine Compounds Ltd

Inventors

• Croitoru Bertha
• Beruben Dov
• Peled Michael
• Rachmilevitch Yaakov
• Hirschsohn Yaniv
• Epshtein Assor Yelena
• Rapaport Ella
• Kopel Dan

Classifications

• C08L2201/02

  Flame or fire retardant/resistant · CPC title

• C08F220/24 Primary

  containing perhaloalkyl radicals · CPC title

• D06M15/263

  of unsaturated carboxylic acids; Salts or esters thereof · CPC title

• C08L33/16

  Homopolymers or copolymers of esters containing halogen atoms · CPC title

• C08L33/14

  of esters containing halogen, nitrogen, sulfur, or oxygen atoms in addition to the carboxy oxygen · CPC title