The Crystallisation, Microphase Separation and Mechanical Properties of the Mixture of Ether-Based TPU with Different Ester-Based TPUs

Abstract

The difference in compatibility at the molecular level can lead to a change of microphase separation structure of thermoplastic polyurethanes blend systems, which will improve their thermal and mechanical properties. In this study, TDI-polyester based TPU was blended with MDI-polyether-based TPU and MDI-polyester based TPU, with different ratios. In the blend system, the obvious reduction of the melting temperature of the high-temperature TDI-polyester based TPU component indicates its hard segments can be mutually integrated with the other component. For TDI-polyester based TPU/MDI-polyether based TPU blends, their similar hard segment ratio and similar chemical structure of the soft segment give the molecular chains of the two components better compatibility. The aggregation structure of the two kinds of chains can rearrange at the molecular level which makes the hard domains mutually integrate to form a new phase separation structure with larger phase region distance. As a result, the yield strength of this blend increased by almost 143% when the elongation at break was only reduced by 12%. In contrast, the other group of blends still partly maintain their respective micro domains, forming a weak interface and leading to a decreased of elongation at break.

Analysis of Thermoplastic Copolymers by Mild Thermal Degradation Coupled to Ion Mobility Mass Spectrometry

“…Gel permeation chromatography (GPC) experiments reported in previous studies had indicated high molecular weights ( M w >150 000 Da) and broad molecular weight distributions ( M w / M n > 2.0) for the TPUs [ 53 ] and thermoplastic styrene–butadiene copolymers [ 54,55 ] examined. These materials exhibited low glass transition temperatures, in keeping with their elastomeric properties.…”

The Influence of Long-Time Storage on the Structure and Properties of Multi-Block Thermoplastic Polyurethanes Based on Poly(butylene adipate) Diol and Polycaprolactone Diol

“…For PBA-based TPUs the crystallization kinetics and crystal phase composition was analyzed as a result of competition between the nucleation and crystal phase growth, from one side, and phase separation efficiency above the melting point of PBA and linear, aromatic and cycloaliphatic urethane blocks, from the other side. In general, for TPU the phase separation of hard and soft blocks that governs the final morphology, mechanical and thermal properties [ 12 , 13 ]. The incompatibility between the blocks can be finetuned not only by changing the composition and ratio of soft and hard segments but also by variation of hydrogen bonding caused by addition of nanofillers or by use of specific thermal programs [ 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ].…”

Preparation, Structure and Properties of Urethane-Containing Elastomers Based on Epoxy Terminal Oligomers

“…The structure of soft segments is defined by oligodiols used for SPU synthesis [ 8 ]. Hard segments are formed by the reaction of isocyanate terminated compounds, oligodiisocyanates, with low molecular weight chain extenders diamines or diols [ 9 ].…”