Patent ID: 11873378
Assignee: NOURYON CHEMICALS INTERNATIONAL B.V.
Field: Other special machines (Mechanical engineering)
Classification: CPC C  B | IPC B  C

Claim 0:
1. Thermally expandable microspheres having a size of from 1 to 100 microns, exhibiting a Tstart of from about 220° C. to about 250° C., and comprising:
a thermoplastic polymer shell encapsulating a blowing agent that is isopentane, isooctane, or combinations thereof, wherein the thermoplastic polymer shell comprises a copolymer of:
α-methylene-γ-valerolactone (MVL) and/or α-methylene-γ-butyrolactone (MBL), and
a co-monomer selected from the group consisting of acrylonitrile, methacrylonitrile, and combinations thereof,
wherein the weight percent of the α-methylene-γ-valerolactone (MVL) and/or the α-methylene-γ-butyrolactone (MBL) is from about 50 up to less than 100 parts by weight, and the weight of the co-monomer is from greater than zero up to about 50 by weight, each based on 100 parts by weight of the co-polymer.