Silicone surfactant/organofunctional polysiloxane internal mold release agents

A liquid for use in preparing reaction injected molded polyurethane or polyurea resins having improved mold release properties which comprises a polysiloxane mold release agent which consists essentially of 0.5-20 mol percent of R.sub.a R'.sub.b SiO.sub.[4-(a+b)]/2 units and from 80-99.5 mol percent of R".sub.c SiO.sub.(4-c)/2 units where R is an isocyanate reactive organic radical, a has an average value of from 1-3, R' and R" are both non-isocyanate reactive organic radicals, b has an average value of 0-2, a+b is from 1-3, and c has an average value of from 1-3, wherein

• the ratio of the total molecular weight to the total number of isocyanate reactive functional groups in the molecule ranges from 100-3500,
• the combined formula weights of all isocyanate reactive organic radicals, R do not exceed 40% of the total molecular weight of said polysiloxane mold release agent,
• the combined formula weights of all non-isocyanate reactive radicals, R'+R" together do not exceed 40% of the total molecular weight of said polysiloxane mold release additive,
• the combined formula weights of all the organic radicals R+R'+R" in the molecule together do not exceed 60% of the total molecular weight of the molecule,
• said polysiloxane mold release agent contains an average of at least two isocyanate reactive functional groups per molecule,
• at least two of the isocyanate reactive functional groups in each molecule are located on separate organic radicals, R, attached independently to different silicon atoms in said polysiloxane,
• said isocyanate reactive functional groups (R) are selected from the group consisting of alcohols, phenols, thiols, primary or secondary aromatic amines, which contain no oxygen, and not more than one nitrogen, atoms attached directly to, in conjugation with, or incorporated within, the aromatic ring nucleous, and secondary aliphatic amines wherein at least one of the alkyl carbon atoms, bonded directly to the nitrogen atom, is not a primary carbon atom and carboxylic acids,
• the molecular weight of said polysiloxane mold release agent ranges from 1000 and 30,000, and
• said polysiloxane mold release agent being substantially insoluble in said liquid polyisocyanate, and from 1-25 percent based on the weight of said polysiloxane mold release agent of a liquid silicone surfactant substantially free of isocyanate reactivity.