Synthesis of Hyperbranched Poly(ester)s with Pendant Hydroxy Groups by the Polyaddition of Bis(oxetane)s with 1,3,5-Benzenetricarboxylic Acid

Abstract

ABSTRACT:Hyperbranched poly(ester)s with many pendant primary hydroxy groups were prepared in 21-84% yields by polyadditions of certain bis(oxetane)s such as 1,4-bis [(3-ethyl-3-oxetanylmethoxymethyl)]benzene (BEOB), 1,2-bis [(3-ethy-3-oxetanyl)methoxy]benzene (1,2-BEOMB), 1,3-bis [(3-ethy-3-oxetanyl)methoxy]benzene (1,3-BEOMB), 1,4-bis [(3-ethy-3-oxetanyl) Oxetanes as 4-membered cyclic ether have almost the same strain energy 1 (107 kJ/mol) as 3-membered cyclic ether oxiranes. Furthermore, basicities of oxetanes were generally higher than those of oxiranes. Therefore, numerous studies 2 of the cationic polymerization of oxetane compound have been reported. The first commercial polymer of oxetane was PENTONE Ò , which was prepared by the ring-opening polymerization of 3,3-bis(chloromethyl)oxetane. Very recently, Motoi and his coworkers 3-5 found certain cationic isomerization reactions of oxetane compounds.However, any other useful ring-opening reactions of oxetane have not been reported excepting our recent research works.6 Since more than 15 years ago, my research group have studied the development of new ring-opening addition reaction of oxetane and succeeded in finding new reactions of oxetanes such as ringopening addition reactions with acyl chlorides, 7 phosphonyl chlorides, 8 silyl chloride, 9 active esters, 7 carboxylic acids, 10 phenols, 11,12 and thiols 13 using appropriate quaternary onium salts or crown ether complexes as catalysts. These reactions can be applied practically to the polyadditions of bis(oxetane)s with above reagents such as diacyl chlorides, 14-17 phosphonyl dichlorides, 8 active diesters, 18,19 dicarboxylic acids, 10 bisphenols, 11,12 and dithiols 13 to afford corresponding polymers with high molecular weights. Recently, we also found that an anionic ring-opening polymerization of 2-(hydroxymethyl)oxetanes produced corresponding hyperbranched poly(ether)s containing one terminal oxetanyl groups and many pendant primary hydroxy groups using the complex of potassium t-buthoxide with crown ether as a catalyst system, [20][21][22] and an anionic ring-opening alternating copolymerization 23 of oxetanes with cyclic carboxylic anhydrides using certain quaternary onium salts as catalysts.The above reaction systems of oxetane compounds and the oxetane polymers prepared by the reactions seem to have great possibility as an important key technology in coatings and electronics fields, and polymer industry in general.Meanwhile, hyperbranched polymers (HBPs) have recently attracted a great deal of attention as one of the dendritic macromolecules, which have lower viscosity, good solubility and many reactive terminal groups compared with the corresponding linear ones. 24 There are many synthetic methods for the preparation of the HBPs, such as vinyl polymerization 25 and ring-opening polymerization 26 accompanying suitable chain transfer reaction. Furthermore, although HBPs are prepared by the step-wise polymerizations such as polycondensations and polyadditions, in which there are two differential...

Hyperbranched and Highly Branched Polymer Architectures—Synthetic Strategies and Major Characterization Aspects

“…Other aliphatic A 2 + B 3 systems have been described by Fossum et al who used glycerol or trimethylolpropane as B 3 monomers and fumaric acid as A 2 monomer, which led to an unsaturated hb polyester. Hyperbranched polyesters with many pendant hydroxyl groups that were in situ modified with acrylate functions were prepared by polyaddition of bisoxetanes to 1,3,5-benzene tricarboxylic acid in NMP solution followed by addition of monofunctional methacrylic acid (Scheme ) . Similarly, hyperbranched polyesters with terminal methacryloyl groups and medium molar mass were synthesized by the one-pot polyaddition of bisphenol A diglycidyl ether and trimesic acid in the presence of methacrylic acid in good yields .…”

“…Hyperbranched polyesters with many pendant hydroxyl groups that were in situ modified with acrylate functions were prepared by polyaddition of bisoxetanes to 1,3,5-benzene tricarboxylic acid in NMP solution followed by addition of monofunctional methacrylic acid (Scheme 25). 291 Similarly, hyperbranched polyesters with terminal methacryloyl groups and medium molar mass were synthesized by the one-pot polyaddition of bisphenol A diglycidyl ether and trimesic acid in the presence of methacrylic acid in good yields. 292 The addition of a monofunctional B molecule to an A 2 + B 3 approach allows control of gelation.…”

Synthesis of Photocrosslinkable Hyperbranched Polyesters with Terminal Methacryloyl Groups by the One-pot Polyaddition of Bis(oxetane)s with 1,3,5-Benzenetricarboxylic Acid and Methacrylic Acid

“…It was found that P-1a was hyperbranched polymer with pendant primary hydroxy groups in the side chain. Detail reaction conditions and results have been reported 18 in the previous paper. This means that the controlled reaction time and feed ratios of these polyaddition can offer the soluble hyperbranched polymer on the reaction of bis(oxetane) with TMA.…”

“…Given these background, we designed 18 new hyperbranched poly(ester)s with pendant primary hydroxy groups as reactive groups by the polyaddition reaction of bis(oxetane)s with 1,3,5-benzenetricarboxylic acid (TMA). However, there are no reports on the synthesis of photo-curable and alkaline developable hyperbranched polymers excepting our recent two papers, 11,19 although alkaline development property is a very important factor in practical application.…”

Catalytic reactions of oxetanes with protonic reagents and aprotic reagents leading to novel polymers

“…82 The reaction of 1,4-bis[(3-ethy-3-oxetanyl)methoxy]-benzene (1,4-BEOMB) and TMA was carried out using certain quaternary onium salts as catalysts at 140 8C for 12 h. These conditions and results are summarized in Table 5.…”