Abstract A novel cyanato-group-containing phenol resin is produced by reacting a cyanogen halide in an inert organic solvent in the presence of a base with a phenol novolak comprising a mixture of polymers represented by the formula, ##STR1## WHEREIN, N IS 0 OR AN INTEGER OF 1 OR MORE; AND R's may be the same or different, and each R represents a hydrogen atom or a methyl group, and containing 50 % by weight or more in total of polymers having the above formula in which n is an integer of 1 to 3, the number average molecular weight of said novolak being at least 300 and less then 600. This phenol resin is suitable for use in the production of a cured resin having outstanding thermal properties.
A cyanato-group-containing phenol resin comprising a mixture of polymers represented by the formula: ##STR5## wherein n is 0 or an integer of 1 or more; and R's may be the same or different, and each R is a hydrogen atom or a methyl group, and containing 50% by weight or more in total of polymers having formula in which n is an integer of 1 to 3, the number average molecular weight of said phenol resin being 350 to 700, as determined by gel permeation chromatography using tetrahydrofuran as solvent.
Claim 2
Dependent Claim
90 words
A cyanato-group-containing phenol resin comprising a mixture of polymers represented by the formula: ##STR5## wherein n is 0 or an integer of 1 or more; and R's may be the same or different, and each R is a hydrogen atom or a methyl group, and containing 50% by weight or more in total of polymers having formula in which n is an integer of 1 to 3, the number average molecular weight of said phenol resin being 350 to 700, as determined by gel permeation chromatography using tetrahydrofuran as solvent.
Claim 3
Dependent Claim
18 words
A cyanato-group-containing phenol resin according to claim 1, wherein the number average molecular weight is 500 to 700.
Claim 4
Dependent Claim
18 words
A cyanato-group-containing phenol resin according to claim 1, wherein the number average molecular weight is 500 to 650.