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硬質(zhì)多孔聚氨酯彈性體的制備及性能分析畢業(yè)論文-資料下載頁

2025-06-24 17:59本頁面
  

【正文】 earch Institute of Yantai Wanhua Polyurethane Co. Ltd. 102200)Abstract: The hard porous polyurethane elastomer was prepared by diphenylmethanediisocyanate (MDI), polytetramethylene ether glycol (PTMEG), polypropylene oxide triol, and methylenebisorthochloroaniline (MOCA) as extender. A kind of expansible microspheres was introduced into the elastomers to get a prehensive properties with low density, high rigidity and high modulus. It has investigated the effects of the contents of hard segments, 2,4MDI isomer, the triol and the microspheres on the mechanical properties of casting elastomers, which was then characterized by SEM, DSC, DMA and tensile testing, respectively. The results indicated that the tensile strength, elastic modulus and dynamic mechanical properties of the elastomers increased dramatically while the elongation at break decreased by increasing hard segments contents, and the optimal value of it would be %。 some certain content (. 25%) of 2,4MDI could increase the elongation at break of the elastomer with little derease of strength properties。 besides, the optimal content of the expansible spheres would be % to get a proper surface hardness and toughness of such polyurethane elastomers.Key words: polyurethane。 porous。 hard elastomers。 mechanical properties作者簡介: 韓艷,女,工程師,主要研究方向:聚氨酯彈性體應(yīng)用基礎(chǔ)研究。通訊聯(lián)系人: 周青,男,高級工程師,北京科聚化工新材料有限公司 分析中心主任,電話:01059659032,Email: zhouqing@,通訊地址:北京昌平科技園區(qū)星火街5號,郵編:10
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