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 浙江大學玉泉校區高分子大樓421房間
  • 郵編:310027
  • 電話:0571-87953732
  • 傳真:0571-87953732
  • Email:xhzhang@zju.edu.cn
當前位置:> 首頁 > 最新動態 > 正文
博士生羅銘在Macromolecules上發表關于二硫化碳和氧雜環丁烷共聚的文章

Abstract: The catalytic coupling of oxetane, the symmetric isomer of propylene oxide, with carbon disulfide has been investigated utilizing (salen)CrCl in the presence of various onium salts. Oxygen and sulfur atom exchange was observed in both the polymeric and cyclic carbonate products. The coupling of oxetane and CS2 was selective for copolymer formation over a wide range of reaction conditions. Five different polymer linkages and two cyclic products were determined by 1H and 13C NMR spectroscopy, and these results were consistent with in situ infrared spectroscopic monitoring of the process. The major cyclic product produced in the coupling process was trimethylene trithiocarbonate, which was isolated and characterized by single crystal X-ray crystallography. Upon increasing the CS2/oxetane feed ratio, a decrease in the O/S scrambling occurred. The reaction temperature had the most significant effect on the O/S exchange process, increasing exchange with increasing temperature. The presence of the onium salt initiator both accelerated the coupling process and promoted O/S scrambling. COS (observed), and CO2 intermediates are proposed in the reactions leading to various polymeric linkages.

文章來源:Macromolecules 2015, 48, 5526-5532.

主站蜘蛛池模板: 汉川市| 连城县| 长顺县| 丹寨县| 海阳市| 红原县| 乌审旗| 榕江县| 玉林市| 天水市| 沂南县| 金堂县| 荣昌县| 施甸县| 巴南区| 赤水市| 长治市| 鄂托克旗| 永康市| 新余市| 上栗县| 万安县| 武乡县| 洛南县| 瑞丽市| 蒲江县| 诏安县| 长岭县| 曲阳县| 都兰县| 长宁县| 安溪县| 沙田区| 广安市| 辉南县| 五家渠市| 三原县| 潢川县| 抚顺市| 山丹县| 象山县|