Process for the production of pneumatic tires having particularly high dynamic strength
AssigneeBayer Aktiengesellschaft
InventorsOtto Ganster, Jurgen Schwindt
Life of this patent
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Abstract
The instant invention is directed to a process for the production of pneumatic tires having particularly high dynamic strength and low plastic deformability comprising casting or centrifugally casting the following liquid reaction system whose rapid hardening requires temperatures of at most 85.degree. C.: (A) prepolymers or semiprepolymers of specified isocyanates and a polyol or polyol mixture having a hydroxyl functionality of 2.0 to 2.2 and an average molecular weight of from 1,000 to 3,000, wherein the molar ratio of polyol to diisocyanate is from 1:1.5 to 1:4.0, (B) specific aromatic diamine chain extenders, (C) catalysts, and (D) auxiliaries.
Claims12
A process for the production of pneumatic tires having particularly high dynamic strength and low plastic deformability comprising casting, or centrifugally casting, the following liquid reaction system whose rapid hardening requires temperatures of at most 85.degree. C.:
- (A) prepolymers or semiprepolymers of
- (i) an isocyanate selected from the group consisting of:
- (a) hexamethylene-1,6-diisocyanate,
- (b) 2,4- or 2,6-tolylene diisocyanate and mixtures thereof,
- (c) 4,4'- or 2,4'-diisocyanato-diphenylmethane and mixtures thereof, and
- (d) diisocyanato-diphenylmethane C.sub.1 -C.sub.4 alkylated from one to four times in the ortho position to the NCO-groups and
- (ii) a polyol or polyol mixture, having a hydroxyl functionality of 2.0 to 2.2 and an average molecular weight of 1,000 to 3,000 consisting of a single component or obtained by mixing several polyols having a molecular weight of 500 to 4,000,
- wherein the molar ratio of polyol to diisocyanate is from 1:1.5 to 1:4.0;
- (B) aromatic diamine chain extenders selected from the group consisting of:
- ##STR13## wherein R.sub.1 and R.sub.2, which may be the same or different, represent C.sub.2 H.sub.5 --, C.sub.3 H.sub.7 -- and C.sub.4 H.sub.9 --;
- ##STR14## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4, which may be the same or different, represent C.sub.2 H.sub.5 -- and C.sub.3 H.sub.7 --;
- and ##STR15## wherein R.sub.1, R.sub.2 and R.sub.3, which may be the same or different, represent C.sub.2 H.sub.5 --, C.sub.3 H.sub.7 -- and C.sub.4 H.sub.9 --
- (C) catalyst;
- and
- (D) auxiliaries.
A process for the production of penumatic tires having particularly high dynamic strength and low plastic deformability comprising casting, or centrifugally casting, the following liquid reaction system whose rapid hardening requires temperatures of at most 85.degree. C.:
- (A) prepolymers or semiprepolymers of
- (i) an isocyanate selected from the group consisting of:
- (a) hexamethylene-1,6-diisocyanate,
- (b) 2,4- or 2,6-tolylene diisocyanate and mixtures thereof,
- (c) 4,4'- or 2,4'-diisocyanato-diphenylmethane and mixtures thereof, and
- (d) diisocyanato-diphenylmethane C.sub.1 -C.sub.4 alkylated from one to four times in ortho position to the NCO-groups and
- (ii) a polyol or polyol mixture, having a hydroxyl functionality of 2.0 to 2.2 and an average molecular weight of 1,000 to 3,000 consisting of a single component or obtained by mixing several polyols having a molecular weight of 500 to 4,000, wherein the molar ratio of polyol to diisocyanate is from 1:1.5 to 1:4.0;
- (B) an aromatic diamine chain extender of the general formula:
- ##STR24## wherein R is C.sub.n H.sub.2n+1,
- n is an integer of from 4 to 10, and
- X is CH.sub.3 -- or Cl;
- (C) catalyst;
- and
- (D) auxiliaries.
Dependencies are inferred from the claim text.