A Thiol- ene Clickable Hyperbranched Polyester via a Simple Single- Step Melt Trans- Esterification Process

作者：Varaprasad N S Shree; Venkhatesh Prasanna; Ramakrishnan S^*

来源：Journal of Applied Polymer Science, 2014, 131(10).

DOI：10.1002/app.40248

• dendrimers
• hyperbranched polymers and macrocycles
• differential scanning calorimetry
• polyesters
• functionalization of polymers

Self-condensation of AB(2) type monomers (containing one A-type and two B-type functional groups) generates hyperbranched (HB) polymers that carry numerous B-type end-groups at their molecular periphery; thus, development of synthetic methods that directly provide quantitatively transformable peripheral B groups would be of immense value as this would provide easy access to multiply functionalized HB systems. A readily accessible AB(2) monomer, namely diallyl, 5-(4-hydroxybutoxy)isophthalate was synthesized, which on polymerization under standard melt-transesterfication conditions yielded a peripherally clickable HB polyester in a single step; the allyl groups were quantitatively reacted with a variety of thiols using the facile photoinitiated thiol-ene reaction to generate a wide range of derivatives, with varying solubility and thermal properties. Furthermore, it is shown that the peripheral allyl double bonds can also be readily epoxidized using meta-chloroperoxybenzoic acid to yield interesting HB systems, which could potentially serve as a multifunctional cross-linking agent in epoxy formulations.

• 出版日期2014-5-15