Photonic crystals in biology - NanoTR-VI

Poster Session, Thursday, June 17Theme F686 - N1123The Maleimide Modified Epoxy Resins for the Preparation of UV-Curable Hybrid CoatingsZerrin Altınta *, Sevim Karata¸ Nilhan Kayaman-Apohan and Atilla GüngörMarmara University, Department of Chemistry 34722 Istanbul/TurkeyAbstract: In the present study, maleimide-modified epoxide resin containing UV-curable hybrid coating materials were prepared and coatedon polycarbonate substrates in order to improve their surface properties. The coating formulations with different compositions were preparedfrom UV-curable bismaleimide-based epoxy oligomer and sol–gel mixture. The thermal and morphological properties of these coatingsmaterials were investigated by using TGA and SEM techniques. The thermal characteristics of UV curable hybrid films were found to bebetter than without Bismaleimide and sol-gel precursor.Polymers of N-substituted maleimides and theirderivatives having a rigid imide ring in the backbone areknown as high performance polymers. Among them,bismaleimides (BMIs) have attracted much attentionbecause of their high-temperature resistance, high glasstransitiontemperature, excellent chemical and corrosionresistance, and low cost. Bismaleimide resins are anaddition-type polyimide class of macromolecularcompounds produced from bismaleimide monomers andcontain unsaturated end groups. Bismaleimides cappedprepolymers are cured into a highly cross-linked networkby additional reactions without the evolution of volatileby-products. However, due to their high cross-link density,they are often brittle, resulting in low impact and fracturetoughness. Introduction of a long, flexible epoxy chain intothe backbone of bismaleimides is expected to reduce crosslinkdensity and also to improve fracture toughness bydissipating the impact energy along the entire molecularchain [1].Currently, to meet the demand of highly miniaturizedelectronic devices, non-linear optical applications, and thedevelopment of next generation spacecrafts, furtherimprovement in the high performance polymers is needed.Organic–inorganic hybrid coatings offer the opportunity tocombine the desirable properties of organic polymers(elasticity, processability) and inorganic solids (hardness,chemical inertness, and thermal resistance). Close to theexcellent properties of the obtained coatings,photopolymerization process itself affords advantages suchas very high reaction rates at room temperature and spatialcontrol of polymerization. These materials manifest someadvantages such as low optical propagation loss, highchemical, and mechanical stabilities as well as goodcompatibility with different surfaces to be coated [2-3].Hence, in this work, a novel bismaleimide wassynthesized by the reaction of cycloaliphatic diepoxidewith N-(carboxyphenyl) maleimide. Afterwards, thehybrid coatings based on UV-curable bismaleimide cappedcycloaliphatic epoxy oligomer were prepared by sol–gelmethod to investigate the coating properties. The hybridmaterials were characterized by analysis of hardness,gloss, adhesion, and stress–strain. The thermal andmorphological behaviors of the coating were alsoevaluated.Table 1. TGA analysis of coating networksSamples60CF25CF-35BMI25CF-35BMI-5Si25CF-35BMI-10Si25CF-35BMI-15SiFirstweightloss( O C)355360355360355Max.weightloss( O C)445445445445445Finalweightloss( O C)595625630635645In conclusion, a series of UV-curable organic-inorganichybrid coatings were prepared based on sol–gel reactionsfor TEOS and MAPTMS in the presence of epoxymodified Bismaleimide oligomer (BMI) and urethaneacrylate oligomer (UA). Incorporation of bismaleimidemodified epoxy resin into the organic part stronglyincreased the thermal resistance of hybrid samples. Uponincreasing the inorganic content of the coating material,thermal, mechanical, and other properties, such ashardness, gloss, contact angle, and abrasion resistance,were also improved. Corona-treated polycarbonate testpanels facilitated the adhesion of the coating materials. Allhybrid coatings were obtained crack-free and transparent.Furthermore, the increase in the contact angle data of thehybrid coatings demonstrated the formation ofhydrophobic surface.*Corresponding author: altintas_zerrin@hotmail.com[1] F. Yılmaz, L. Cianga, Y. Gu¨ ner, L. Toppare, Y. Yacı,Polymer, 45, 5765, (2004).[2] H. Tang, W. Li, X. Fan, X. Chen, Z. shen, O. Zhou, Polymer,50,1414 (2009).[3] L. A. White, J. W. Weber, L. J. Mathias, Polym. Bulletin , 46,339, (2001).6th Nanoscience and Nanotechnology Conference, zmir, 2010 708