Abstract
A systematic study was conducted to investigate the effect of hard segment molecular weight on concentrated solution and bulk properties of thermoplastic ether based polyurethanes (TPUs). The molar feed was used to determine the molecular weight of the hard segment. Then the weight fraction of the hard segment is determined by calculating the ratio of the molecular weight of the hard segment to the number average molecular weight of the TPU determined by GPC. Similar to the study of dilute solution properties, it was found that thermal and mechanical properties in the bulk were significantly affected at low weight fractions of the hard segment. The critical weight fraction of the hard segment was found at about 0.4. Above critical weight fraction of hard segment there is a diminishing effect on the thermal properties and dynamical/ mechanical properties in bulk.
Highlights
Many useful polyurethane devices are made from liquids, via solution,dispersion, emulsion, or suspension
We report the highlights of our study on the effect of hard segment molecular weight on concentrated solutions and bulk properties such as rheological, thermal, and mechanical properties in Regions 2 and 3
The weight fraction of the hard segment is the ratio of the molecular weight of the hard segment to the number average molecular weight of the thermoplastic ether based polyurethanes (TPUs) determined by GPC [1,2,3,4,5]
Summary
Many useful polyurethane devices are made from liquids, via solution,dispersion, emulsion, or suspension. The purpose of this study is to provide a roadmap to deliver the desired end-use performance of a polyurethane product based on the optimal design of the starting materials. Such a roadmap shown, illustrates a bottom-up approach to study the effect of hard segment length (i.e., molecular weight) on properties of a polyurethane material from a very dilute solution to bulk [1,2,3]. We report the highlights of our study on the effect of hard segment molecular weight on concentrated solutions and bulk properties such as rheological, thermal, and mechanical properties in Regions 2 and 3
Published Version (Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have