Polymeric shaped articles

A process for preparing a tractable shaped article of simple profile capable of being further shaped and cured into an intractable shaped article, said process comprising the steps of:

• A. preparing a homogeneous mixture consisting essentially of
• a. from 5% to 95% by weight of polyurethane precursors free of ethylenic unsaturation comprising
• 1. at least one polyol or hydroxy-terminated polyester containing hydroxy groups reactive with isocyanate groups wherein the hydroxy groups of said polyol or polyester polyurethane precursors are the only polyurethane precursor substituents reactive with isocyanate groups, and
• 2. at least one polyisocyanate of the structure ##STR4## wherein X is a divalent radical containing at most three atoms in the chain between the phenyl groups in said structure, or a mixture comprising at least 40% by weight of the total polyisocyanate of at least one polyisocyanate having the structure I with at least one other polyisocyanate, said polyurethane precursors being capable of forming if cured alone in the absence of precursors of cured polyester resin a cross-linked polyurethane having a glass-rubber transition temperature of at least 25.degree. C, as measured with a DuPont 900 thermal analyzer, the rate of heating the sample being 20.degree. C per minute, at least one of said polyol, hydroxy-terminated polyester or other polyisocyanate being tri-functional or of higher functionality;
• and
• b. from 95% to 5% by weight of precursors of cured polyester resin consisting essentially of
• 3.

at least one ethylenically unsaturated polyester containing in each molecule at least two hydroxy or carboxylic acid groups reactive with isocyanate groups, and

• 4. at least one vinyl monomer containing at least one ethylenically unsaturated group which will react with ethylenically unsaturated groups in the polyester, said precursors of cured polyester resins comprising from 40-90% by weight of (3) and from 60-10% by weight of (4) and said vinyl monomer being selected from the group consisting of styrene, methyl methacrylate, divinyl benzene, diallyl phthalate and vinyl toluene;
• B. polymerizing said mixture in a mould to a degree such that a tractable
• partially polymerized article is obtained. 3. A process for preparing a tractable shaped article capable of being further shaped and cured into an intractable shaped article, said process comprising the steps of:
• A. preparing a homogeneous mixture consisting essentially of
• a. from 5% to 95% by weight of polyurethane precursors free of ethylenic unsaturation comprising
• 1. at least one polyol or hydroxy-terminated polyester containing hydroxy groups reactive with isocyanate groups wherein the hydroxy groups of said polyol or polyester polyurethane precursors are the only polyurethane precursor substituents reactive with isocyanate groups, and
• 2. at least one polyisocyanate compound of the structure ##STR5## wherein X is a divalent radical containing at most three atoms in the chain between the phenyl groups in said structure, or a mixture comprising at least 40% by weight of the total polyisocyanate of at least one polyisocyanate having the structure I with at least one other polyisocyanate, said polyurethane precursors being capable of forming if cured alone in the absence of precursors of cured polyester resin a cross-linked polyurethane having a glass-rubber transition temperature of at least 25.degree. C, as measured with a DuPont 900 thermal analyzer, the rate of heating the sample being 20.degree. C per minute, at least one of said polyol, hydroxy-terminated polyester or other polyisocyanate being tri-functional or of higher functionality;
• and
• b. from 95% to 5% by weight of precursors of cured polyester resin consisting essentially of
• 3. at least one ethylenically unsaturated polyester containing in each molecule at least two hydroxy or carboxylic acid groups reactive with isocyanate groups, and
• 4. at least one vinyl monomer containing at least one ethylenically unsaturated group which will react with ethylenically unsaturated groups in the polyester, said precursors of cured polyester comprising from 40-90% by weight of (3) and from 60-10% by weight of (4) and said vinyl monomer being selected from the group consisting of styrene, methyl methacrylate, divinyl benzene, diallyl phthalate and vinyl toluene;
• B. shaping said mixture and reacting said polyurethane precursors without substantial reaction between said polyester and vinyl monomer to obtain said shaped tractable article.