PURPOSE: To obtain a polythiourethane, having a specific recurring unit, capable of manifesting excellent mechanical or optical properties and useful as an optical material, a cross-linking agent, a curing agent, etc., for epoxy resins.
CONSTITUTION: This polythiourethane comprises a recurring unit of formula I [R is H or acetyl; (n) is 2-12]. The polythiourethane is obtained by reacting, e.g. a compound of formula II (the one prepared by dropping carbon disulfide into a mixed solution of, e.g. bisphenol S diglycidyl ether with lithium bromide and tetrahydrofuran and carrying out the reaction at ambient temperature) with a 1,ω,-(2-12C)alkanediamine in the presence (absence) of a solvent such as chloroform or tetrahydrofuran at 0-120°C temperature under atmospheric pressure or a slight pressure.
TOCHIGI HIDEFUMI
OMURA HIROSHI
SUYAMA SHUJI
Next Patent: POLYTHIOURETHANE