Study On The Surface Confined Condensation Polymerization And Synthesis/Property Of A Novel Multifunctional Epoxy

Surface photo-grafting has been considered as a promising way to prepare a kind of film on the surface of which there are acids groups and novel reactive groups. The catalysis curing reactions of phenolic resole and stepwise grafting reactions induced by confined acids and novel groups were studied to explore and understand the basic principles. Meanwhile, a novel multi-phenol and new novel epoxy compound was synthesized, and their structures and thermo-resi stance property were analyzed and characterized. The main achievements are as following:The films with carboxyl group on the surface were prepared by the UV photo-grafting of acrylic acid onto LDPE films. Resultant surface confined acid can catalyze the curing reaction of phenolic resole. Calculated thickness of curing phenolic resole layer was between 20nm and 60nm. The reaction time and reaction temperature dependence of catalysis curing effect of confined acid on phenolic resole demonstrated that the thickness of curing phenolic resole layer increased slightly, which clarified the catalytic effect of confined carboxyl groups on the curing of phenolic resole were not power enough.The films with sulfonic groups on the surface were prepared by the reaction of carboxyl groups in LDPE-g-PAA and sulfanic acid with conversation of carboxyl groups more than 30%. The viscosity of phenolic solution kept constant when films were soaked into the solution, which revealed the curing reaction of phenolic resole occurred only on the surface or the vicinity of sulfonic groups in stead of in the solution of phenolic resole. The weight and the thickness of cured phenolic resole layer on the surface of films were increased with the increase of reaction temperature and reaction time. Cured phenolic resole layer was increased from 127nm to 234nm when the reaction time changed from 1 hour to 10 hours at 50℃, and from 87nm to 154nm when the reaction temperature rose from 22℃to 50℃. The catalysis effect of acid on the curing of phenolic resole varied obviously with the variation of solubility of solvent. The thickness of curing phenolic resole layer thickened from 40nm to 90nm with increase of reaction time in water. Otherwise, the thickness of curing phenolic resole was only between 20nm to 30nm in acetone in the condition as the same as that in water. Consequently, an appropriate model of confined sulfonic acid was proposed. H proton was confined within a distance of L to a sulfonic group, which was influenced by reaction temperature and solubility of solvent. The value of L enlarged with the rise of temperature and better of solubility of solvent. This model can explain experimental phenomena reasonably.The films with acyl chloride on the surface were prepared by the reaction of LDPE-g-PAA and thionyl chloride. The reaction conditions were determined. The comparison of stability of obtained acyl chloride in several kinds of solvents was carried out and acetone was found to be appropriate one where the acyl chloride existed stably. The confined acyl chloride groups were used to graft resorcinol molecule successfully, which was expected to be a position for further condensation with some monomers with functional groups, such as formaldehyde and acetone. A new way was designed to undergo the stepwise grafting reaction by which resorcinol and formaldehyde (or acetone) was grafted alternatively to the surface of LDPE film. This method was also useful way for theoretical study of stepwise polymerization.A new way was invented for preparation of a tri-functional phenol by using resorcinol and acetone in water. It was of the feature of simple composition, high purity of product (more than 94%) and high monomer conversion (more than 99%). An appropriate mechanism of the reaction of resorcinol and acetone was proposed. Furthermore, tri-functional group phenol was used to make epoxy by reaction with epichlorohydrin. The structure and molecular weight measured by FTIR and ESI-MS clarified the synthesized epoxy compound was a corresponding tri-functional epoxy (TF-EPOXY). Then, kinetic study of curing behavior of this TF-EPOXY cured by DDS and DDM was determined. Suitable curing temperature and curing activation energy were determined by DSC analytical results which were 200℃-250℃and 63．2kJ/mol for TF-EPOXY/DDS system and 150℃-200℃and 55．3kJ/mol for TF-EPOXY/DDM system respectively. Finally, the properties of heat resistance of TF-EPOXY / DDS and TF-EPXOY/DDM were elucidated by DSC, DMTA and TG analysis. The experimental results showed that Tg of TF-EPOXY/DDS system and CYD128/DDM were both more than 300℃, which were 100℃higher than that of BIS-A epoxy system. The synthesized novel epoxy compound was new species with thermo-resistance and high property.