Polymer, process and composition

摘要

There are described vinyl sequential copolymers (and processes for making them) comprising (a) at least 8. 5 wt-% preferably >=20 wt-% of a higher itaconate diester (preferably dibutyl itaconate -DBI); (b) less than 23 wt-% acid monomer but also sufficient to have an acid value less than 150 mg KOH/g of polymer, (c) optionally with less than 50 wt-% of other itaconate monomers, and (d) optionally less than 77 wt-%of other monomers not (a) to (c). The DBI may be biorenewable. One embodiment is an aqueous dispersion of the vinyl sequential polymer of two phases: A) 40 to 90 wt-% of a vinyl polymer A with Tg from -50 to 30°C; and B) 10 to 60 wt-% of a vinyl polymer B with Tg from 50 to 130°C; where DBI is used to prepare A and/or B and polymer A has from 0.1 to 10 wt-% of at least one acid-functional olefinically unsaturated monomer.