Polysiloxane foam compositions and methods related thereto

A curable organopolysiloxane foam-forming composition comprising:

• (A) 100 parts by weight of an organopolysiloxane represented by the average unit formula:
• wherein, R is a substituted or unsubstituted monovalent hydrocarbon group, and “a” is a number from 1.0 to 2.4, and having at least an average of 1.5 alkenyl groups in a molecule;
• (B) from 1 to 70 parts by weight an organopolysiloxane having at least an average of 1.5 silicon-bonded hydrogen atoms in a molecule;
• (C) from 0.1 to 50 parts by weight of a blowing agent;
• and
• (D) from 0.00001 to 20 parts by weight of a particle comprising:
• i. a platinum-group catalyst;
• and
• ii. a molecular weight controlled thermoplastic polymer having a Tg or softening temperature of at least 20° C. selected from the group consisting of:
• 1. polystyrene or a co-polymer thereof having a Mw from about 500 g/mol to about 30,000 g/mol, and a polydispersity index (PDI) of less than 2;
• 2. polymethylmethacrylate or a co-polymer thereof having a Mw from about 500 g/mol to about 30,000 g/mol, and a PDI of less than 2;
• and
• 3. polyacrylonitrile or a co-polymer thereof having a Mw from about 500 g/mol to about 30,000 g/mol, and a PDI of less than 2:
• wherein the platinum-group catalyst is fully encapsulated within the thermoplastic polymer.