Multistage polymer powder composition, its method of preparation and use

Patent metadata

Field	Value
Publication number	US-2017183457-A1
Application number	US-201515301805-A
Country	US
Kind code	A1
Filing date	Apr 7, 2015
Priority date	Apr 7, 2014
Publication date	Jun 29, 2017
Grant date	—

Abstract

The present invention relates to halogenated containing polymer composition with a modifier that is a polymeric processing aid in form a non dusty polymer powder made by a multistage process while the last stage uses ethyl acrylate as major monomer.

First claim

1 . A polymer composition in the form of polymeric particles comprising
at least one stage forming a layer (B) comprising a polymer (B1) having a glass transition temperature of at least 60° C. and at least one stage forming a layer (A) comprising a polymer (A1) having a glass transition temperature of less than 60° C. and wherein polymer (A1) comprises at least 50 wt % of polymeric units coming from ethyl acrylate, obtained by a multistage process wherein the weight ratio r of the layer (A) in the composition comprising the two layers is at least 2 wt %.

2 . The polymer composition according to claim 1 wherein the layer (A) comprising a polymer (A1) having a glass transition temperature of less than 60° C. is a stage forming an outer layer of the polymeric particles.

3 . The polymer composition according to claim 1 wherein the layer (B) comprising a polymer (B1) having a glass transition temperature of at least 60° C. is a stage forming an inner layer of the polymeric particles.

4 . The polymer composition according to claim 1 wherein the weight ratio r in wt % of the layer (A) comprising polymer (A1) in the complete polymer particle for a Tg between 200K and 333K of the polymer (A1) is at least a defined by following formula
r=b 1 e a 1 T
wherein the variable T is the glass transition temperature T g expressed in Kelvin of the polymer (A1) of the external layer (A) and the exponent al is at least 0.0255 and the factor b 1 is at least 0.0055 and the exponent a1 is at most 0.028 and the factor b1 is at most 0.007.

5 . The polymer composition according to claim 1 wherein the weight ratio r in wt % of the layer (A) comprising polymer (A1) in the complete polymer particle is at most 30 wt %.

6 . The polymer composition according to claim 1 wherein the polymer (A1) is a (meth) acrylic polymer comprising at least 60 wt % of monomers coming from acrylic or methacrylic monomers.

7 . The polymer composition according to claim 6 wherein the acrylic or methacrylic monomers of the polymer (A1) are chosen from the group consisting of methyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, tert-butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate and mixtures thereof.

8 . The polymer composition according to claim 1 wherein the glass transition temperature Tg of the polymer (A1) is between −50° C. and 50° C.

9 . The polymer composition according to claim 1 wherein the polymer (B1) is a (meth) acrylic polymer.

10 . The polymer composition according to claim 1 wherein the polymer (B1) comprises at least 70 wt % monomers chosen from the group consisting of C1 to C12 alkyl (meth)acrylates.

11 . The polymer composition according to claim 1 wherein the polymer (B1) comprises acrylic or methacrylic monomers that are chosen from the group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate and mixtures thereof.

12 . The polymer composition according to claim 1 wherein the glass transition temperature Tg of the polymer (B1) is between 60° C. and 150° C.

13 . The polymer composition according to claim 1 wherein the mass average molecular weight Mw of the polymer (A1) is less than 1 000 000 g/mol.

14 . The polymer composition according to claim 1 wherein the mass average molecular weight of the polymer (B1) is at least 300 g/mol.

15 . A method for manufacturing the polymer composition comprising the steps of:
a) polymerizing by emulsion polymerization of a monomer or monomer mixture (B m ) to obtain layer (B) comprising a polymer (B1) having a glass transition temperature of at least 60° C., and b) polymerizing by emulsion polymerization of a monomer or monomer mixture (A m ) to obtain one layer (A) comprising polymer (A1) having a glass transition temperature of less than 60° C. wherein weight ratio r of the obtained layer (A) in the composition comprising the two layers is at least 2wt % and the monomer mixture (Am) comprises at least 50 wt % of ethyl acrylate.

16 . The method according to claim 15 , wherein the weight ratio r in wt % of the layer (A) comprising polymer (A1) in a complete polymer particle for a Tg between 200K and 333K of the polymer (A1) is at least a defined by formula.
r=b 1 e a 1 T wherein the variable T is the glass transition temperature Tg expressed in Kelvin of the polymer (A1) of the external layer (A) and the exponent a1 is at least 0.0255 and the factor b1 is at least 0.0055 and the exponent a1 is at most 0.028 and the factor b1 is at most 0.007.

17 . The method according to claim 15 the wherein step a) is made before step b).

18 . The method according to claim 15 wherein step b) is performed in presence of the polymer (B) obtained in step a).

19 . The method according to claim 15 wherein the method comprises an additional drying step c) by spray drying.

20 . A halogenated containing polymer composition comprising
a) a halogenated polymer and b) a polymer obtained by a multistage process with
at least one stage forming an inner layer (B) comprising a polymer (B1) having a glass transition temperature of at least 60° C. and
at least one stage forming an outer layer (A) comprising a polymer (A1) having a glass transition temperature of less than 60° C. and polymer (A1) comprises at least 50 wt % of polymeric units coming from ethyl acrylate,
weight ratio r of the outer layer (A) in the polymer obtained by a multistage process comprising the two layers is at least 2 wt %.

21 . (canceled)

22 . (canceled)

23 . (canceled)

Assignees

• Arkema France

Inventors

• Pirri Rosangela
• Schipper Christiaan A
• Hajji Philippe

Classifications

• C08L27/06

  Homopolymers or copolymers of vinyl chloride · CPC title

• C08L51/003

  grafted on to macromolecular compounds obtained by reactions only involving unsaturated carbon-to-carbon bonds (C08L51/04, C08L51/06 take precedence) · CPC title

• C08J2433/08

  Homopolymers or copolymers of acrylic acid esters · CPC title

• C08J2333/12

  Homopolymers or copolymers of methyl methacrylate · CPC title

• C08L101/04

  containing halogen atoms · CPC title