Synthesis of a photocrosslinkable hyperbranched polyester containing methacryloyl groups by the reaction of 1,4-bis(chloromethyl)benzene with 1,3,5-benzenetricarboxylic acid followed by reaction with methacrylic acid

Abstract

The synthesis and photo-polymerization of hyperbranched polyesters (HBPEs) containing terminal methacryloyl groups (HBPE-MA) were examined. Polycondensations of 1,4-bis(chloromethyl)benzene with 1,3,5-benzenetricarboxylic acid using 1, 8-diazabicyclo[5.4.0]undec-7-ene as a base were performed to give the soluble HBPEs in satisfactorily high yields. Furthermore, HBPE-MA was synthesized by the reaction of HBPE with methacrylic acid. The photo-induced radical polymerization of HBPE-MA was performed in the presence of 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-2-one (Irgacure 907), which acts as a photoinitiator in the solid film state and yields an insoluble cured film upon ultraviolet irradiation. Polymer Journal (2010) 42, 790-794; doi:10.1038/pj.2010.74Keywords: DBU; hyperbranched polymer; photoradical polymerization; polyester INTRODUCTION Radiation-curing technology has been widely used in many applications such as adhesives, aerospace, electronics, printing, auto refinishing and ultraviolet (UV) inkjets. 1-3 These technologies, which are based on radical reactions using (meth)acrylated monomers and oligomers such as (meth)acrylated epoxy resin, polyurethane and polyester, are mainly used due to their high performance. Recently, research on the new applications of radiation-curing technology has also been reported. Shirai et al. 4 reported on a negative-tone photo-resist for extreme UV lithography based on radical reactions using multifunctional thiol compounds and poly(4-hydroxystyrene) containing C¼C double bonds such as (meth)acryloyl groups.Alternately, hyperbranched polymers (HBPs) attract attention due to their unique properties such as lower viscosity, 5,6 good solubility 7 and a large number of terminal functional groups compared with the corresponding linear ones. HBPs can be synthesized by two methods: one is the self-polymerization of AB 2 -type monomers; 8-10 the other is the copolymerization of an A 2 -type monomer with a B 3 -type monomer. 11,12 The latter has a significant advantage for industrial applications because commercially available monomers can be used as the starting materials.There have been many reports on the synthesis and characterization of HBPs. Ueda et al. 13 reported on the synthesis of a HBP, with an

Synthesis of hyperbranched polyacetals via a n + b2 -type polyaddition (n = 3, 8, 18, and 21): Candidate resists for extreme ultraviolet lithography

“…Further, the A n + B m ‐type method has significant advantages for industrial applications, because commercially available monomers can be used, and soluble hyperbranched polymer can be synthesized in high yield by control of the polymerization conditions, such as monomer feed ratio, monomer concentration, and reaction time. Many hyperbranched polymers have been reported: hyperbranched polyamide, hyperbranched polyesters, hyperbranched polyimide, hyperbranched polybenzoxazole, and hyperbranched polyacetal . Very recently, Ramakrishnan et al reported the synthesis of a photodegradable hyperbranched polyacetal by means of an AB 2 ‐type method.…”

Conversion Reaction of Benzyl-Type Chlorinated Hydrocarbons into Functional Groups

“…But the toxic reagent is not good to operator and environment. The reaction with carboxyl groups catalyzed by DBU as a base is also common with short reaction time, simple postprocessing, high selectivity and yield, but the side chain such as hydroxyl would affect the selectivity 21 .…”