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:常州大學(xué)材料科學(xué)與工程學(xué)院
  • Zip:213164
  • Tel:18261185351
  • Fax:
  • Email:cloudyyang@cczu.edu.cn
Current Location :> Home > Publications > Text
Preparation, characterization and thermal degradation behavior of rigid polyurethane foam using a malic acid based polyols
writer:RongYang, BoWang, MengdiLi, XinZhang, JinchunLi
keywords:Bio-based polyols, Malic acid, Rigid polyurethane foam, Thermal degradation behavior
source:期刊
specific source:Industrial Crops and Products
Issue time:2019年

A series of multi-functionality polyester polyols (MAP) were synthesized successfully by using a renewable resource of malic acid and 1,6-hexanediol via esterification. The chemical structure of MAP was characterized by proton nuclear magnetic resonance (1H NMR), Fourier-transform infrared (FTIR), gel permeation chromatography (GPC) as well as acid and hydroxyl values. Then it was used to prepare rigid polyurethane foams (RPUFs). The results suggested that MAP based RPUFs showed lower density (37?39?kg/m3), compressive strength (154?156?kPa) and better insulation (0.019?0.025?W/(m·K)) than that of the commercial petrochemical polyol. Moreover, thermal degradation behavior of MAP based RPUF were demonstrated by thermogravimetric analysis (TGA), thermogravimetric analysis connected with Fourier transform infrared spectrometry (TG-FTIR) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) in detail. It indicated that as a bio-resource polyol, MAP could totally substitute petrochemical polyol to prepare RPUF with a good comprehensive performance. https://doi.org/10.1016/j.indcrop.2019.04.073