Melamine resin polymers exhibit high transmittance, high pencil hardness, and high refractive index. However, high temperatures and long reaction times are required to obtain the desired condensation products. In this study, acrylic-modified melamine resins were synthesized that were cured by irradiation with ultraviolet (UV) light. The synthesized acrylic-modified melamine resins could be cured rapidly due to the radical reaction of the acrylic groups and retained high transparency and high refractive index as features of the melamine resin polymers. The polymerized film by UV curing had low shrinkage and high refractive index. Compared with general multifunctional moiety-type acrylic monomers such as pentaerythritol triacrylate and dipentaerythritol hexaacrylate, the acrylic-modified melamine resins had the same degree of hardness. In addition, flexibility, a feature of the urethane moiety, was imparted to the polymer by the reaction of residual hydroxyl groups with isocyanate.

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In this study, transparent poly(methylmethacrylate) (PMMA)-silicone hybrid materials, P(MMA-coSigUMAx), were prepared with methylmethacrylate (MMA) and multifunctional silicone macromonomer introduced methacryl groups. The transmittance of hybrid materials improved with increase of methacryl groups of silicone macromonomer and reached around 90% T. Atomic force microscopic analysis, scanning electron microscope examinations, and copolymerization kinetics estimation by proton nuclear magnetic resonance revealed that the silicone macromonomer randomly incorporated in the copolymer with MMA by the increase of methacryl groups and suppresses the aggregation of the silicone segment. The hybrid materials introduced over 10 wt % of silicone component had watershedding surface and the water contact angle was elevated from 65 to 95. Though the mechanical properties of hybrid materials were lowered by introduction of flexible silicone component, thermal property such as 5 wt % weight loss temperature were improved.

The aim of this study was the preparation of novel water repellent UV curable materials using acrylic modified melamine (AM) and poly-dimethylsiloxane (PDMS). UV curable acrylic melamines containing silicone segments (SiAMs) were synthesized by condensation of methylolmelamine, 2-hydroxyethyl acrylate, and carbinol-modified PDMS. The SiAM films with a 0.3 wt% PDMS segment that were cured by UV irradiation had higher transparency than that of a blended sample. Examination with a scanning electron microscope revealed that the blend sample has cohesion of the silicone segments, while such a phenomenon was not observed in the composite samples (SiAMs). From these results, it was confirmed that aggregation of the silicone segments was prevented by introducing the silicone segments into the acrylic melamine. By introducing 0.3 wt% of PDMS segments into AM, good watershedding properties were confirmed, while several of the most attractive features of AM, such as hardness, adhesion, and refractive index, were maintained.