Effect of chain architecture of polyol with secondary hydroxyl group on aggregation structure and mechanical properties of polyurethane elastomer. (5th May 2017)

• Record Type: Journal Article
• Authors: Nozaki, Shuhei; Hirai, Tomoyasu; Higaki, Yuji; Yoshinaga, Kohji; Kojio, Ken; Takahara, Atsushi
• Is Part Of: Polymer. Volume 116(2017)
• Page Start: 423
• Page End: 428
• Publication Date: 2017-05-05
• Subjects: Polyurethane elastomer -- Polyol -- Secondary hydroxyl group -- Microphase-separated structure -- Mechanical property; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; 547.7
• DOI: 10.1016/j.polymer.2017.03.031
• Languages: English
• ISSNs: 0032-3861

Abstract

Abstract: Polyurethane elastomers (PUEs) based on poly(2-ethyl-1, 3-hexamethylene adipate) glycol (PEHA), poly(2, 4-diethyl-1, 5-pentamethylene adipate) glycol (PDEPA) and poly(2-butyl-2-ethyl-1, 3-trimethylene adipate) glycol (PBETA) were synthesized with 4, 4'-diphenylmethane diisocyanate (MDI) and 1, 4-butane diol (BD)/1, 1, 1-trimethylol propane (TMP). PEHA has one primary and one secondary hydroxyl groups, but PDEPA or PBETA has two primary hydroxyl groups. The effect of low reactive secondary OH group on molecular aggregation structure and mechanical properties of the PUEs was investigated using Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS), dynamic viscoelastic measurement and tensile testing. The study demonstrates that PEHA-based PUE has lower cross-linking density and lower degree of microphase separation than PDEPA- and PBETA-based PUEs. As a result, PEHA-based PUE has lower dynamic storage modulus value at the rubbery plateau region and Young's modulus. Graphical abstract: Highlights: A reactivity difference in secondary and primary hydroxyl groups of polyol was utilized for control of a network structure for polyurethane. Secondary hydroxyl group gave lower degree of microphase separation and network density, and dangling chains. Controls of a network structure and mechanical property of polyurethane have been attained.