Chloroprene copolymer latex composition and molded product thereof

Patent metadata

Field	Value
Publication number	US-11427701-B2
Application number	US-201817276537-A
Country	US
Kind code	B2
Filing date	Sep 26, 2018
Priority date	Sep 26, 2018
Publication date	Aug 30, 2022
Grant date	Aug 30, 2022

Abstract

There is provided a chloroprene copolymer latex composition capable of obtaining a molded product having excellent mechanical properties and flexibility even when vulcanized and molded under milder conditions than before. A chloroprene copolymer latex composition contains a chloroprene copolymer latex (A), a metal oxide (B), a vulcanization accelerator (C), and an antioxidant (D). The chloroprene copolymer latex (A) is a latex containing particles of a chloroprene copolymer which is a copolymer of chloroprene (A-1), 2,3-dichloro-1,3-butadiene (A-2), and sulfur (A-3). The content of the sulfur (A-3) in the chloroprene copolymer is 0.1 part by mass or more and 1.0 part by mass or less when the total amount of the chloroprene (A-1) and the 2,3-dichloro-1,3-butadiene (A-2) is set to 100 parts by mass.

First claim

The invention claimed is:

1. A chloroprene copolymer latex composition comprising:
a chloroprene copolymer latex (A), a metal oxide (B), a vulcanization accelerator (C), and an antioxidant (D), wherein
the chloroprene copolymer latex (A) is a latex containing particles of a chloroprene copolymer which is a copolymer of chloroprene (A-1), 2,3-dichloro-1,3-butadiene (A-2), and sulfur (A-3),
a content of the sulfur (A-3) in the chloroprene copolymer is 0.1 part by mass or more and 1.0 part by mass or less when a total amount of the chloroprene (A-1) and the 2,3-dichloro-1,3-butadiene (A-2) is set to 100 parts by mass, and
a content of a tetrahydrofuran insoluble content in the chloroprene copolymer is 50% by mass or more and 85% by mass or less.

2. The chloroprene copolymer latex composition according to claim 1 , wherein
a copolymerization ratio of the chloroprene (A-1) is 76% by mass or more and 93% by mass or less and a copolymerization ratio of the 2,3-dichloro-1,3-butadiene (A-2) is 24% by mass or less and 7% by mass or more when the total amount of the chloroprene (A-1) and the 2,3-dichloro-1,3-butadiene (A-2) is set to 100% by mass.

3. The chloroprene copolymer latex composition according to claim 1 , wherein
when an amount of a solid content in the chloroprene copolymer latex (A) is set to 100 parts by mass, an amount of the metal oxide (B) is 1 part by mass or more and 10 parts by mass or less, an amount of the vulcanization accelerator (C) is 0.1 part by mass or more and 5 parts by mass or less, and an amount of the antioxidant (D) is 0.1 part by mass or more and 5 parts by mass or less.

4. A molded product, which is the chloroprene copolymer latex composition according to claim 1 , wherein
a 300% modulus of elasticity is 0.5 MPa or more and 1.6 MPa or less, a tensile strength is 18 MPa or more, and a tensile elongation at break is 800% or more.

5. The molded product according to claim 4 , which is a dipped product.

6. The molded product according to claim 5 , which is a glove.

7. The molded product according to claim 5 , which is a medical disposable glove.

8. The chloroprene copolymer latex composition according to claim 2 , wherein
when an amount of a solid content in the chloroprene copolymer latex (A) is set to 100 parts by mass, an amount of the metal oxide (B) is 1 part by mass or more and 10 parts by mass or less, an amount of the vulcanization accelerator (C) is 0.1 part by mass or more and 5 parts by mass or less, and an amount of the antioxidant (D) is 0.1 part by mass or more and 5 parts by mass or less.

9. A molded product, which is the chloroprene copolymer latex composition according to claim 2 , wherein
a 300% modulus of elasticity is 0.5 MPa or more and 1.6 MPa or less, a tensile strength is 18 MPa or more, and a tensile elongation at break is 800% or more.

10. A molded product, which is the chloroprene copolymer latex composition according to claim 3 , wherein
a 300% modulus of elasticity is 0.5 MPa or more and 1.6 MPa or less, a tensile strength is 18 MPa or more, and a tensile elongation at break is 800% or more.

11. The chloroprene copolymer latex composition according to claim 1 , wherein particles of the chloroprene copolymer are dispersed in water.

12. A method of producing a chloroprene copolymer latex composition comprising:
adding chloroprene (A-1), 2,3-dichloro-1,3-butadiene (A-2) and sulfur (A-3) to obtain chloroprene copolymer latex (A) containing particles of a chloroprene copolymer, and
stirring the chloroprene copolymer latex (A), a metal oxide (B), a vulcanization accelerator (C), and an antioxidant (D) to obtain the chloroprene copolymer latex composition,
wherein a content of a tetrahydrofuran insoluble content in the chloroprene copolymer is 50% by mass or more and 85% by mass or less, and
wherein a content of the sulfur (A-3) in the chloroprene copolymer is 0.1 part by mass or more and 1.0 part by mass or less when a total amount of the chloroprene (A-1) and the 2,3-dichloro-1,3-butadiene (A-2) is set to 100 parts by mass.

13. The method according to claim 12 , wherein particles of the chloroprene copolymer are dispersed in water.

14. The method according to claim 12 , wherein chloroprene (A-1), 2,3-dichloro-1,3-butadiene (A-2) and sulfur (A-3) are added at a same time.

Assignees

• Showa Denko Kk

Inventors

• Murata Tomoaki
• Ogawa Noriko
• Kamijo Masanao

Classifications

• C08K3/22 Primary

  of metals · CPC title

• C08K5/31

  Guanidine; Derivatives thereof · CPC title

• C08K5/13

  Phenols; Phenolates · CPC title

• A41D19/0062

  made of one layer of material · CPC title

• A61B42/10

  Surgical gloves · CPC title