6533b872fe1ef96bd12d2cae

RESEARCH PRODUCT

Synthesis of reactive hyperbranched and star-like polyethers and their use for toughening of vinylester–urethane hybrid resins

Jörg FröhlichRolf MülhauptO. GryshchukJózsef Karger-kocsisHolger FreyHolger Kautz

subject

chemistry.chemical_classificationToughnessMaterials sciencePolymers and PlasticsScanning electron microscopeOrganic ChemistryPolymerDynamic mechanical analysisBranching (polymer chemistry)chemistry.chemical_compoundchemistryMaterials ChemistryPolymer blendComposite materialThermal analysisPolyurethane

description

A vinylester – urethane hybrid resin (VEUH) was toughened by adding various vinyl-functionalized branched polyethers in 10 and 20 wt%. Two sets of hyperbranched polymers (HBPs) with different branching density were compared with a set of six-arm star polymers. Besides the architecture, the polymers also varied in their characteristics (molecular mass and mass distribution, vinyl/hydroxy ratio). The morphology of the modified VEUH was studied by dynamic-mechanical thermal analysis (DMTA), transmission (TEM) and scanning electron microscopy (SEM). The toughness was characterized by the fracture energy ðGcÞ determined on compact tension specimens at room temperature. It was established that the architecture and vinyl/hydroxy ratio of the HBPs are those parameters which control the morphology and thus the related linear elastic fracture mechanical response. Less compact star-like polymers with long, flexible arms and with high vinyl functionality produced the largest toughness improvement in VEUH. q 2003 Elsevier Ltd. All rights reserved.

yearjournalcountryeditionlanguage
2004-02-01Polymer
https://doi.org/10.1016/j.polymer.2003.12.050