Synthesis of 1,1,3,3,5,5-hexamethyl-1,5-bis[(3-ethyl-3-methoxyoxetane)propyl]trisiloxane and Research on Its UV-curing Performance

Abstract

A compound, 3-ethyl-3-hydroxymethyloxetane (EHO), was synthesized with diethyl carbonate and trihydroxypropane as raw materials, 3-ethyl-3-allylmethoxy oxetane (EAMO) was synthesized with EHO and allyl bromide, and 1,1,3,3,5,5-hexamethyl-1,5-bis[(3-ethyl-3-methoxyoxetane)propyl]trisiloxane (HMBEMOPTS) was synthesized with EAMO and 1,1,3,3,5,5-hexamethyltrisiloxane (HMTS). HMBEMOPTS is a novel UV-curable oligomer. The test of photo-DSC shows the photosensitivity of HMBEMOPTS is better than the ordinary oxetane, 3-ethyl-3-[(3-ethyloxetan-3-yl)methoxymethyl]oxetane. HMBEMOPTS was mixed with bisphenol A type epoxy resin E-51 to prepare a cationic UV-curable system, and triarylsulfonium hexafluoroantimonate (UV-6976) was used as a cationic photoinitiator. The mechanical tests of coating films prove that when the mass fraction of HMBEMOPTS is 50%, the mechanical properties of the curing system are the best. The impact strength of the UV-curable films is measured to be 40 kg-cm and the flexibility is 2 mm; the tensile strength and flexural strength of the prepared specimens are 20.74 MPa and 13.43 MPa, respectively. The experimental results show that HMBEMOPTS can effectively improve photosensitivity and flexibility of the photosensitive resin.

Keywords

oxetane / siloxane / photosensitive resin