Process for producing thermoplastic moulding compositions with improved mechanical properties

Patent metadata

Field	Value
Publication number	US-9982123-B2
Application number	US-201515300389-A
Country	US
Kind code	B2
Filing date	Apr 1, 2015
Priority date	Apr 2, 2014
Publication date	May 29, 2018
Grant date	May 29, 2018

Abstract

The invention relates to a process for producing molding compositions containing: a) from 55 to 85% by weight of copolymer A composed of vinylaromatic monomer A1 and a,B-unsaturated monomer A2; b) from 15 to 45% by weight of graft copolymer B with particle size from 50 to 550 nm composed of: B1: from 60 to 80% by weight of rubbery graft base B1 composed of: B11: from 80 to 99% by weight of at least one C2-C8-alkyl acrylate, B12: from 0.5 to 2.5% by weight of cyclic crosslinking agent, B13: from 0 to 2% by weight of non-cyclic crosslinking agent, B2: from 20 to 40% by weight of at least one graft shell B2 composed of: B21: from 60 to 75% by weight of a styrene, B22: from 25 to 40% by weight of acrylonitrile, c) from 0 to 10% by weight of additives C; where the reaction time of the polymerization for producing the graft base B1 is in the range from 2 to 5 h, and the addition of the starting materials takes place over at least two chronological segments.

First claim

What is claimed is:

1. A process for the production of a thermoplastic molding composition comprising:
a) from 55 to 85% by weight of at least one copolymer A composed of at least one vinylaromatic monomer A1, and also at least one α,β-unsaturated monomer A2;
b) from 15 to 45% by weight of at least one graft copolymer B with average particle size from 50 to 550 nm, composed of:
from 60 to 80% by weight of at least one rubbery graft base B1 consisting of:
B11: from 80 to 99% by weight of at least one C2-C8-alkyl acrylate,
B12: from 0.5 to 2.5% by weight of a cyclic crosslinking agent selected form dicyclopentadienyl acrylate,
B13: from 0 to 2.0% by weight of a noncyclic crosslinking agent comprising at least two functional groups,
B14: from 0 to 18% by weight of a further copolymerizable monomer; and from 20 to 40% by weight of at least one graft shell B2 consisting of:
B21: from 60 to 75% by weight of an optionally substituted styrene,
B22: from 25 to 40% by weight of acrylonitrile,
B23: from 0 to 9% by weight of a further copolymerizable monomer;
c) from 0 to 10% by weight of other auxiliaries and/or additives C;
where the entirety of components A to C provides 100% by weight of the molding composition, and where the reaction time of the polymerization for the production of the graft base B1 is in the range from 2 to 5 h, and addition of mixture of components B11, B12, B13, and B14 for the production of B1 takes place over at least two chronological segments.

2. The process for the production of a thermoplastic molding composition as claimed in claim 1 , where the production of the graft base B1 is achieved by carrying out a free-radical polymerization in emulsion, and addition of the monomer mixture of B11 and B12 takes place over at least two chronological segments.

3. The process for the production of a thermoplastic molding composition as claimed in claim 1 , where production of the graft base B1 is achieved by using the following steps:
a) initiation of the polymerization of C2-C8-alkyl acrylate (B11) in the presence of the cyclic crosslinking agent (B12),
b) emulsification of the mixture from a),
c) reaction of the graft base B1 with at least one graft shell B2,
d) continued polymerization of the mixture from c) and optionally filtration.

4. The process for the production of a thermoplastic molding composition as claimed in claim 1 , where addition of a monomer mixture made of B11 and B12 for the production of B1 takes place over at least three chronological segments.

5. The process for the production of a thermoplastic molding composition as claimed in claim 1 , characterized in that the time for each of the segment additions for the production of B1 is in the range from 20 to 60 min.

6. The process for the production of a thermoplastic molding composition as claimed in claim 1 , characterized in that a quantity of from 1 to 2% by weight, based on component B1, of dicyclopentadienyl acrylate (DCPA) is used as cyclic crosslinking agent B12.

7. The process for the production of a thermoplastic molding composition as claimed in claim 1 , characterized in that copolymer A is a copolymer of styrene (A11) and of acrylonitrile (A12) with molecular weight Mw in the range from 20 000 g/mol and 300 000 g/mol.

8. The process for the production of a thermoplastic molding composition as claimed in claim 1 , characterized in that copolymers A and B are mixed with from 0.5 to 5% by weight of other auxiliaries and/or additives C.

9. A thermoplastic molding composition produced by the process as claimed in claim 1 .

10. A method of use of the thermoplastic molding composition obtained by the process as claimed in claim 1 for the production of moldings, films, fibers, or coatings, wherein the thermoplastic molding composition is processed by extrusion, injection molding, or calendaring.

11. A molding, film, fiber, or coating which is produced from the molding composition obtained by the process as claimed in claim 1 .

12. The process for the production of a thermoplastic molding composition as claimed in claim 5 , characterized in that the time for each of the segment additions is in the range from 20 to 40 min.

Assignees

• Ineos Styrolution Group Gmbh

Inventors

• Kopping Jordan
• Boeckmann Philipp
• Niessner Norbert
• Behring Lydia

Classifications

• C08L25/12 Primary

  with unsaturated nitriles · CPC title

• C08L2203/16

  used for films · CPC title

• C08L2203/12

  used for fibers · CPC title

• C08F265/06

  Polymerisation of acrylate or methacrylate esters on to polymers thereof · CPC title

• C08F265/04 Primary

  on to polymers of esters · CPC title