Process for the production of condensation polymers via in-reactor chain extension and products thereof

A method comprising:

• adding a chain extender during the polymerization process of a polyester to provide a chain-extended polyester, wherein the chain extender comprises a polymerization product of
• at least one epoxy-functional (meth)acrylic monomer, and
• at least one styrene monomer, substituted styrene monomer, (meth)acrylic monomer, or a mixture of any two or more thereof;
• wherein:
• the polymerization process is a batch polymerization process or a continuous polymerization process;
• the chain extender is added when the solution intrinsic viscosity of the condensation polymer is no more than about 0.6 dL/g;
• and
• a molecular weight of the chain-extended condensation polymer is achieved in a time that is less than the time to achieve the molecular weight in the absence of the chain extender;
• the chain extender is added from about 0.1% to about 0.32% by weight of the total weight of the chain extender and the components of the polyester;
• and
• the polyester is polyethyleneterephthalate.