Method for producing thermoplastic elastomer composition
View Patent ↗A method for producing a thermoplastic elastomer composition comprising using a twin screw kneader to melt-knead a thermoplastic resin and an elastomer; the twin screw kneader having at least two raw material inlets including a first raw material inlet and a second raw material inlet provided at a position separated by 15D to 38D on a downstream side from the first raw material inlet, where D is a cylinder inside diameter of the twin screw kneader; the elastomer being fed in a divided manner from the first and second raw material inlets; a proportion of the elastomer fed from the second raw material inlet being from 10 to 60 vol % of a total amount of the elastomer; and the elastomer being melt-kneaded in a kneading zone having a length of from 0.5D to 20D in a cylinder axis direction of the twin screw kneader.
1. A method for producing a thermoplastic elastomer composition comprising using a twin screw kneader to melt-knead a thermoplastic resin and an elastomer;
the twin screw kneader having at least two raw material inlets including a first raw material inlet and a second raw material inlet provided at a position separated by 15D to 38D on a downstream side from the first raw material inlet, where D is a cylinder inside diameter of the twin screw kneader;
the same elastomer being fed in a divided manner from the first and second raw material inlets;
a proportion of the elastomer fed from the second inlet being from 10 to 60 vol % of a total amount of the elastomer; and
the elastomer being melt-kneaded in a kneading zone having a length of from 0.5D to 20D in a cylinder axis direction of the twin screw kneader, at least one kneading zone being respectively provided between the first and second raw material inlets and on a downstream side from the second raw material inlet;
wherein a temperature (A) of the elastomer fed from the second raw material inlet is at least 100° C. lower than a resin temperature (T) of a cylinder tip discharge port at the time of kneading.
2. The production method according to claim 1 , wherein the total amount of the elastomer is at least 30 parts by volume per 100 parts by volume of a total amount of the thermoplastic resin and the elastomer.
3. The production method according to claim 1 , wherein the elastomer is dynamically crosslinked.
4. The production method according to claim 1 , wherein the elastomer is at least one selected from the group consisting of a brominated isobutylene-p-methylstyrene copolymer, an ethylene-α-olefin copolymer, an ethylene-glycidyl methacrylate copolymer, and an ethylene-ethyl acrylate copolymer.
5. The production method according to claim 1 , wherein the thermoplastic resin is at least one selected from the group consisting of an ethylene-vinyl alcohol copolymer, a polyamide resin, and a polyester resin.
6. A thermoplastic elastomer composition produced by the method according to claim 1 .
7. A pneumatic tire using a film comprising the thermoplastic elastomer composition according to claim 6 .
8. A hose using a film comprising the thermoplastic elastomer composition according to claim 6 .