Polyphenylene sulfide block copolymer and manufacturing method therefor

1. A polyphenylene sulfide block copolymer comprising:

50 to 99% by weight of polyphenylene sulfide units (A); and

50 to 1% by weight of polyorganosiloxane units (B),

provided that the total amount of (A) and (B) is 100% by weight, the polyphenylene sulfide block copolymer having a glass-transition temperature of 80° C. or lower and a weight-average molecular weight of 35,000 to 100,000.

2. The polyphenylene sulfide block copolymer according to claim 1 , wherein the polyorganosiloxane units (B) are polydimethylsiloxane units.

3. The polyphenylene sulfide block copolymer according to claim 1 , wherein the polyorganosiloxane units (B) are contained in an amount of 10 to 40% by weight.

4. The polyphenylene sulfide block copolymer according to claim 1 , wherein the polyphenylene sulfide block copolymer has a weight-average molecular weight of 45,000 to 80,000.

5. A method of producing the polyphenylene sulfide block copolymer according to claim 1 , comprising:

heating a polyphenylene sulfide (A) having a functional group content of 100 μmol/g or more and a polyorganosiloxane (B) having functional groups,

the polyphenylene sulfide (A) being represented by general formula (I):

wherein Z is a reactive functional group selected from a carboxyl group, an amino group, a hydroxyl group, an acid anhydride group, an isocyanate group, an epoxy group, a silanol group, an alkoxysilane group, and derivatives thereof, and m is an integer of 10 or greater.

6. The method according to claim 5 , wherein heating the polyphenylene sulfide (A) and the polyorganosiloxane (B) is carried out in an organic polar solvent.

7. The method according to claim 5 , wherein the polyorganosiloxane (B) having functional groups has, at its ends, reactive functional groups selected from an epoxy group, a carboxyl group, an amino group, a hydroxyl group, an acid anhydride group, an isocyanate group, a silanol group, an alkoxysilane group, and derivatives thereof.

8. The method according to claim 5 , wherein the polyphenylene sulfide (A) having a functional group content of 100 μmol/g or more is a polyphenylene sulfide obtained by heating a mixture comprising at least (i) a sulfidizing agent, (ii) a dihalogenated aromatic compound, (iii) an organic polar solvent, and (iv) a monohalogenated compound having a reactive functional group W, the amount of the monohalogenated compound being 0.01 to 25 mol % per mole of the dihalogenated aromatic compound (ii), the monohalogenated compound being represented by general formula (II):

wherein V represents a halogen.

9. The method according to claim 8 , wherein the reactive functional group of the monohalogenated compound (iv) having a reactive functional group W is a functional group selected from a carboxyl group, an amino group, a hydroxyl group, an acid anhydride group, an isocyanate group, an epoxy group, a silanol group, an alkoxysilane group, and derivatives thereof.

10. The method according to claim 5 , wherein the polyphenylene sulfide (A) is a polyphenylene sulfide obtained by heating a cyclic polyphenylene sulfide (a) in the presence of a sulfide compound having reactive functional groups, the amount of the sulfide compound being 0.01 mol % to 25 mol % per mole of phenylene sulfide structural units, the sulfide compound being represented by general formula (III):

wherein at least one of X and Y is a functional group selected from a carboxyl group, an amino group, a hydroxyl group, an acid anhydride group, an isocyanate group, an epoxy group, a silanol group, an alkoxysilane group, and derivatives thereof, and p represents an integer of 0 to 20, provided that p may be a single integer or a combination of different integers.

11. The method according to claim 10 , wherein the cyclic polyphenylene sulfide (a) is a monomer or a mixture comprising 50% by weight or more of a cyclic polyphenylene sulfide represented by general formula (IV) wherein i is from 4 to 50:

12. The method according to claim 10 , wherein the polyphenylene sulfide (A) is a polyphenylene sulfide obtained by heating a mixture comprising the cyclic polyphenylene sulfide (a) and the sulfide compound having reactive functional groups in the absence of a solvent.

13. The method according to claim 10 , wherein the reactive functional groups of the sulfide compound having reactive functional groups are functional groups selected from an amino group, a carboxyl group, and a hydroxyl group.

14. A molded article comprising the polyphenylene sulfide block copolymer according to claim 1 .