Study on Preparation and Properties of Conducting Polyurethane Nanocomposites

• Main Authors: Jia-Yi Liu, 劉佳宜
• Other Authors: Yen Zem Wang
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/60243431680099629235

博士 === 國立雲林科技大學 === 工程科技研究所博士班 === 94 === Abstract Conducting polyurethane nanocomposites series （PUs）include the functional polyurethane copolymer (oligomer of amine terminated polyaniline，OPA )、the well-dispersed chemically functionalized multi-walled carbon nanotubes (MWNTs) / conducting polyurethane composites and polyaniline（PANI）- polyurethane（with OPA content） networks. Conducting polyurethane were synthesized by a two-stage solution polymerization and characterized by FT-IR and 13C-NMR .Various percentages of OPA as chain extenders or polyol were introduced into polymer structures to form the conducting polyurethane with urea-linkage. 1-Methyl-2-Pyrrolidinone (NMP) solubilizes polyaniline（Pani）and OPA because they could strongly interact with Pani and OPA chains, and plasticizes the cast film between polymer chains through hydrogen bonding The effect of. plasticizers in the Pus can be improved thoroughly Protonation-deprotonation cycles（PDC）to remove NMP. FT-IR spectroscopy and differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) were performed to elucidate the interaction and the degree of miscibility among hard and soft segments .They were relateded to the stress-strain properties of PUs. The degree of degree of miscibility is significantly improved as the OPA concentration in PUs increases. The hydrogen bonding index(HBI) measured by FT-IR was employed to show the degree of interchain hydrogen bonding .Copolymer films with higher OPA content exhibit higher HBI and markedly higher miscibility .The PUs have a higher tensile strength and higher Youngs’ Modulus because of the long rigid structure of OPA and PANI , the greater number of hydrogen bonds created among the copolymers blocks .The incorporation of OPA and PANI in PUs increases the weight of the residue at temperatures of over 600℃ , according to thermogravimetric analysis (TGA). Separation characteristics of membranes are measured by gas permeation . The experimental results show that the networks contain the polyaniline content up to 30 wt% and own high gas selectivity （�哸O2/CH4）over 300. The conductivity of PUs is found to be ranging from 0.83 S / cm for neat OPA to 6.11 × 10-5 S / cm for PUs.