how is hmmm used
It is supplied in liquid form at > 98% non-volatile. It is composed predominantly of monomeric HMMM and lower levels of dimeric and trimeric analogs, which are linked either through methylene, -N-CH2-N-, or methyleneoxy, -N-CH2-O-CH2-, bridges. HMMM is also used as a crosslinking agent with polyurethanes. The polymers known as urethane oils3,4 include materials that incorporate the carbamate functional group as well as other functional groups. In the present article, castor oil5 is used as a hydroxyl group containing polyol and isophorone diisocyanate as polyfunctional diisocyanate.