Process of manufacturing a multistage polymer, its composition, its use and composition comprising it

Patent metadata

Field	Value
Publication number	US-10316127-B2
Application number	US-201515527406-A
Country	US
Kind code	B2
Filing date	Nov 24, 2015
Priority date	Nov 24, 2014
Publication date	Jun 11, 2019
Grant date	Jun 11, 2019

Abstract

The present invention relates to a multistage polymer, its composition, its process of preparation, and its use as impact modifier in thermoplastic compositions. More particularly the present invention relates to a process for manufacturing a polymer composition comprising a multistage polymer and its use as impact modifier in thermoplastic compositions.

First claim

The invention claimed is:

1. A process for manufacturing a polymer composition comprising a multistage polymer comprising the steps of:
a) polymerizing by emulsion polymerization of a monomer or monomer mixture (A m ) to obtain during this stage one layer (A) comprising polymer (A1) having a glass transition temperature of less than 0° C.,
b) polymerizing by emulsion polymerization in presence of the polymer obtained in step a) of a monomer or monomer mixture (B m ) to obtain during this subsequent stage a layer (B) comprising a polymer (B1) having a glass transition temperature of at least 45° C.,
c) coagulating the multistage polymer with an alkali metal salt,
d) washing the multistage polymer,
e) adjusting the pH value after the coagulation to a value between 5 to 10, and
f) addition of an aqueous solution or dispersion comprising a phosphorus containing compound wherein the phosphorus has the oxidation stage of +III or +V,

wherein said polymer composition comprises at least 350 ppm of phosphorus and less than 30 ppm of earth alkali metals as traces or impurities.

2. The process according to claim 1 , wherein step a) and b) use in the emulsion polymerization a surfactant chosen from the group consisting of an anionic surface-active agent.

3. The process according to claim 1 wherein said earth alkali metal salt is a sodium or potassium salt.

4. The process according to claim 1 comprising an additional step g):
drying the polymer composition.

5. The process according to claim 1 wherein said polymer composition comprises at most 2000 ppm of phosphorus that has the oxidation stage of +III or +V.

6. The process according to claim 1 wherein said polymer composition comprises between 350 ppm and 2000 ppm of phophorus that has the oxidation stage of +III or +V.

7. The process according to claim 1 wherein no multivalent cations are voluntarily added.

8. The process according to claim 1 wherein initiator does not contain any voluntarily added earth alkali metals.

9. The process according to claim 1 wherein no earth alkali metals either as ions or in form of salts are voluntarily added during the process.

10. The process according to claim 1 wherein earth alkali metals as traces or minor impurity present less than 9 ppm of the multistage polymer composition.

11. The process according to claim 1 wherein said multivalent cations present less than 50 ppm of the multistage polymer composition.

12. The process according to claim 1 wherein the multivalent cations present less than 20 ppm of the multistage polymer composition.

13. The process according to claim 1 having an adjusted pH after coagulation between 6 and 9.

14. The process according to claim 1 wherein the phosphorous containing compound is chosen from the group consisting of organophosphorus compound, a phosphate salt, phosphoric acid, phosphonate salts, phosphonic acid and their respective esters and mixtures thereof.

15. The process according to claim 1 wherein in step f) the aqueous solution or dispersion comprising a phosphorus containing compound wherein the phosphorus has the oxidation stage of +III or +V is added by washing the multistage polymer which contains less than 60 wt % of water with said aqueous solution or dispersion comprising a phosphorus containing compound wherein the phosphorus has the oxidation stage of +III or +V.

16. The process according to claim 1 wherein in step f) the aqueous solution or dispersion comprising a phosphorus containing compound wherein the phosphorus has the oxidation stage of +III or +V is added on the wet cake after coagulation step and filtration step.

17. The process according to claim 1 wherein in step f) the aqueous solution or dispersion comprising a phosphorus containing compound wherein the phosphorus has the oxidation stage of +III or +V is added during drying step of the multistage polymer, when the multistage polymer composition comprises still at least 10 wt % of water.

18. A process for manufacturing a polymer composition comprising a multistage polymer and a thermoplastic polymer comprising the steps of:
a) polymerizing by emulsion polymerization of a monomer or monomer mixture (A m ) to obtain during this stage one layer (A) comprising polymer (A1) having a glass transition temperature of less than 0° C.,
b) polymerizing by emulsion polymerization in presence of the polymer obtained in step a) of a monomer or monomer mixture (B m ) to obtain during this subsequent stage a layer (B) comprising a polymer (B1) having a glass transition temperature of at least 45° C.,
c) coagulating the multistage polymer with an alkali metal salt,
d) washing the multistage polymer,
e) adjusting the pH value after the coagulation to a value between 5 to 10,
f) addition of an aqueous solution or dispersion comprising a phosphorus containing compound wherein the phosphorus has the oxidation stage of +III or +V,
g) drying the multistage polymer, and
h) mixing the multistage polymer with a thermoplastic polymer wherein said polymer composition comprises at least 350 ppm of phosphorus and less than 30 ppm of earth alkali metals as traces or impurities.

19. A thermoplastic polymer composition comprising the polymer composition obtained by the process according to claim 1 .

Assignees

• Arkema France

Inventors

• Navarro Christophe
• Couffin Aline O
• Pirri Rosangela
• Malet Frederic

Classifications

• C08F279/02 Primary

  on to polymers of conjugated dienes · CPC title

• C08L67/00

  Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain (of polyester-amides C08L77/12; of polyester-imides C08L79/08); Compositions of derivatives of such polymers · CPC title

• C08F279/06 Primary

  Vinyl aromatic monomers and methacrylates as the only monomers · CPC title

• C08F220/10

  Esters · CPC title

• C08L51/04

  grafted on to rubbers · CPC title