Novel thermosetting resin and a process for producing same

A resin composition comprising 1 equivalent of an epoxide having 2 or more of vicinal epoxy groups, 2 equivalent or more of an organic diisocyanate and 0.01 to 10% by weight of a catalyst for forming isocyanurate rings and oxazolidone rings based on the total amount of the epoxide and isocyanate, whereby a thermosetting resin containing as a recurring unit 2 or more isocyanurate rings each being connected through an organic isocyanate residue and an oxazolidone ring connected at one side through an organic isocyanate residue to an isocyanurate ring and having at the other side an epoxy residue is provided by heating at a temperature higher than 80.degree. C at which isocyanurate rings and oxazolidone rings are formed.

A process for producing a thermosetting resin, which comprises heating a resin composition comprising 1 equivalent of an epoxide having 2 or more of vicinal epoxy groups, equivalents or more of an organic polyisocyanate and 0.01 to 10% by weight of a catalyst for forming an isocyanurate ring and oxazolidone ring based on the total amount of the epoxide and organic isocyanate to carry out a trimerization reaction of the isocyanate, and then allowing the trimerized isocyanate to react with the epoxide, whereby a thermosetting resin containing as a recurring unit 2 or more isocyanurate rings each being connected through an isocyanate residue and an oxazolidone ring connected at one side through an isocyanate residue ring and having at the other side an epoxy residue is provided by heating at a temperature greater than 80.degree. C at which isocyanurate rings and oxazolidone rings are formed.

A process for producing a thermosetting resin which comprises heating a resin composition comprising 1 equivalent of an epoxide having 2 or more of vicinal epoxy groups, 2 equivalents or more of an organic diisocyanate and 0.01 to 10% by weight of a catalyst for forming an isocyanurate ring and oxazolidone ring based on the total amount of the epoxide and isocyanate to carry out a trimerization reaction of the isocyanate, and then allowing the trimerized isocyanate to react with the epoxide, whereby a thermosetting resin containing as a recurring unit 2 or more isocyanurate rings each being connected through an isocyanate residue and an oxazolidone ring connected at one side through an isocyanate residue to an isocyanurate ring and having at the other side an epoxy residue is provided by heating at a temperature higher than 80.degree. C at which isocyanurate rings and oxazolidone rings are formed.

A process for producing a thermosetting resin which comprises (a) heating a resin composition comprising 1 equivalent of an epoxide having two or more vicinal epoxy groups, 2 equivalents or more of an organic polyisocyanate and 0.01 to 10% by weight of a catalyst for forming isocyanurate rings and oxazolidone rings based on the total amount of the epoxide and organic isocyanate at a temperature sufficient to carry out a trimerization reaction of the isocyanate so that isocyanurate bonds are predominantly formed, and (b) subsequently heating said composition at a temperature so that oxazolidone bonds are formed so that said resin is threedimensionally cross-linked.

A resin produced by the process comprising (a) heating a resin composition comprising 1 equivalent of an epoxide having two or more vicinal epoxy groups, 2 equivalents or more of an organic polyisocyanate and 0.01 to 10% by weight of a catalyst for forming isocyanurate rings and oxazolidone rings based on the total amount of the epoxide and organic polyisocyanate at a temperature sufficient to carry out a trimerization reaction of the isocyanate so that isocyanurate bonds are predominantly formed, and (b) subsequently heating said composition at a temperature so that oxazolidone bonds are formed so that said resin is three-dimensionally cross-linked.

A resin composition capable of forming a thermoset resin containing as a recurring unit 2 or more isocyanurate rings each being connected through an organic isocyanate residue and an oxazolidone ring connected at one side through an organic isocyanate residue through an isocyanurate ring and having at the other side an epoxy residue by heating at a temperature higher than 80.degree. C at which isocyanurate rings and oxazolidone rings are formed, said resin composition consisting essentially of 1 equivalent of an epoxide having 2 or more vicinal epoxy groups, 2 equivalents or more of an organic polyisocyanate and 0.01 to 10% by weight of a catalyst for forming isocyanurate rings and oxazolidone rings based on the total amount of the epoxide and isocyanate.