Abstract: A low stress agent which increases the coherence of organic materials and an inorganic filler, decreases the modulus in molded articles which absorb stress and impact energy is prepared by a process which comprises preparing a silane-modified reactive liquid polymer from a silane coupling agent and a reactive liquid polymer containing functional groups or double bonds, treating the surface of an inorganic filler with a silane coupling agent, and reacting said silane modified reactive liquid polymer with said treated inorganic filler. An epoxy resin or phenol resin composition which contains the low stress agent is very suitable for use in encapsulating a semiconductor.

Abstract: A suspension or emulsion polymerization process for the preparation of modified resin useful as a low-stress semiconductor encapsulant which comprises reacting a silicone oil or a silicone resin an having at least two silanol groups or hydrolyzable alkoxy groups with a silane coupling agent having at least two hydrolyzable alkoxy groups to form a suspension or emulsion of a reactive intermediate product, azeotropically distilling the resulting suspension or emulsion to produce a distrilled intermediate product, and adding an epoxy resin or a phenol resin to the distilled intermediate product to produce a matrix having insoluble and infusible spherical particles.