Synthesis of a branched photosensitive copolymer and its application for negative‐type photoresists

Abstract

Novel branched copolymers, poly(styrene-alt-maleic anhydride) (BPSMA), were synthesized through mercapto chaintransfer polymerization with styrene, maleic anhydride (MA), and 4-vinyl benzyl thiol (VBT). Then, the hydroxyl of hydroxyethyl methacrylate was reacted with MA to synthesize branched photosensitive copolymers, p-BPSMAs. Fourier transform IR spectroscopy and 1 H-NMR indicated that the synthesis was successful. Gel permeation chromatography indicated that the molecular weight decreased with increasing content of VBT. The thermal properties were characterized by thermogravimetric analysis; the results show that the thermal decomposition temperature of the BPSMAs was greatly enhanced. Real-time IR was used to evaluate the UV-curable kinetics of the p-BPSMAs; the results show that the p-BPSMAs could rapidly photopolymerize under UV irradiation in the presence of photoinitiators. Moreover, the photoresist based on the p-BPSMAs exhibited improved photosensitivity when the VBT content increased, and the photoresist with 12 mol % VBT content had a low value of the dose that retained 50% of the original film thickness (10 mJ/cm 2 ), and a 50-lm resolution could be achieved compared to a linear photoresist.

Study on the effect of reactive diluents on exothermic UV curable and coating films properties

“…Therefore, the UV-curable film prepared by DCPDA has a high gloss. In addition, the glass transition temperature(Tg) reflects the movement ability of molecular chains in UV curing, C and E have higher Tg which densifies the structure of the cured film, and enhances the reflection of the cured film on light which can improve the gloss of the products [6]. As can be seen from Table 4, the best performance in terms of anti-friction properties is E, followed by C and A.…”