私密直播全婐app免费大渔直播,国产av成人无码免费视频,男女同房做爰全过程高潮,国产精品自产拍在线观看

Links
Contact Info.
  • Address:廣州市天河區五山華南農業大學材料與能源學院
  • Zip:510642
  • Tel:13560283795
  • Fax:
  • Email:xuca2020@163.com
Current Location :> Home > Publications > Text
Study on the surface properties and thermal stability of polysiloxane-based polyurethane elastomers with aliphatic and aromatic diisocyanate structures
writer:Chang-An Xu,Mangeng Lu,Zhiyou Tan, Zhencai Qu,Kun Wu,Jun Shi
keywords:Polyurethane,Surface properties,Diisocyanate,Thermal stability, Polysiloxane
source:期刊
specific source:Colloid and Polymer Science
Issue time:2020年

A series of polysiloxane-based polyurethane elastomers with aliphatic and aromatic diisocyanate structures are prepared using a two-step polymerization method. First, tolylene diisocyanate (TDI); dicyclohexylmethane 4,4′-diisocyanate (H12MDI); and hexamethylene diisocyanate (HDI) separately react with polycarbonate diol (PCDL) to produce polyurethane prepolymer, and furthermore, polysiloxane (PDMS) is added to the system to produce different polymers. The effect of different diisocyanate structures on mechanical properties, thermal stability, surface topography, and hydrophobic properties are explored. The results show that when the mass loss is higher than 50% during thermal decomposition, TDIPU exhibits relatively excellent thermal stability, which may be caused by the exposure of the silicone inside the polymer. HDIPU shows high hydrophobicity and low surface free energy, which is mainly related to a large amount of Si enriched on the surface. These differences are mainly caused by different molecular structures.