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

相關鏈接
聯系方式
  • 通信地址:杭州市浙大路38號浙大玉泉校區第十教學大樓(石化大樓)4111室
  • 郵編:310027
  • 電話:0571-87952631
  • 傳真:0571-87951612
  • Email:wulinbo@zju.edu.cn
當前位置:> 首頁 > 最新動態 > 正文
吳彬霜題為“Biobased poly(butylene 2,5-furandicarboxylate) and poly(butylene adipate-co-butylene 2,5-furandicarboxylate)s: From synthesis using highly purified 2,5-furandicarboxylic acid to thermo-mechanical properties”的論文發表在Polymer (2014)
To synthesize high quality (co)polyesters derived from 2,5-furandicarboxylic acid (FA), an acetic acid refluxing/pH-swing method was proposed to purify FA. 2-Carboxyl furfural and other impurities were removed completely from FA with this method. Using highly purified FA, biobased polyester poly(butylene furnadicarboxylate) (PBF) and aliphatic-aromatic copolyesters poly(butylene adipate-co-butylene 2,5-furandicarboxy-late)s (PBAFs) were synthesized via melt (co)polycondensation. The (co)polyesters were characterized with GPC, FTIR, 1H NMR, DSC and TGA, and their tensile mechanical properties were also assessed. The copolyesters possess random chain structure, monomer feed ratio-controlled copolymer composition and excellent thermal stability (Td,5% > 340 oC) in full composition range. Both BA-rich and BF-rich PBAFs are crystalline polymers. The crystallizability decreases with composition, up to nearly amorphous at moderate ?BF (40-60%). PBAFs with ?BF no more than 50% exhibit obvious high-elastic deformation and rebound resilience, and possess tensile properties (E 18-160 MPa, sb 9-17 MPa, eb 370-910%) comparable to poly(butylene adipate). PBAFs with higher ?BF behave like nonrigid plastics with low tensile moduli (42-110 MPa), moderate strength (30-42 MPa) and high elongation at break (310-470%). In comparison, PBF is a strong and tough thermoplastic having balanced mechanical properties, namely, much higher tensile modulus (1.9 GPa) and strength (56 MPa) and high elongation at break (260%). It seems necessary and effective to use highly purified FA for synthesizing high performance FA-derived (co)polyesters.
主站蜘蛛池模板: 孟连| 葵青区| 日照市| 拉萨市| 茌平县| 宿州市| 威信县| 达孜县| 云龙县| 遵义县| 东乡族自治县| 肃宁县| 武邑县| 紫云| 塔城市| 江口县| 分宜县| 临江市| 峨山| 崇阳县| 仪征市| 鄂尔多斯市| 沁源县| 周至县| 封开县| 万荣县| 库车县| 洪湖市| 克山县| 福海县| 铜鼓县| 台东市| 汝城县| 榆树市| 潼关县| 蛟河市| 临武县| 沙田区| 磴口县| 鄂州市| 会理县|