文献类型：期刊文献

中文题名：差示扫描量热法测定紫胶树脂玻璃化转变温度的条件研究

英文题名：Research of Conditions in Determining the Glass Transition Temperature of Lac Resin by Differential Scanning Calorimetry

作者：冀浩博[1,2] 张弘[1] 郑华[1] 孙彦琳[2] 李坤[1]

第一作者：冀浩博

机构：[1]中国林业科学研究院资源昆虫研究所;[2]昆明理工大学化学工程学院

年份：2014

卷号：28

期号：8

起止页码：98-104

中文期刊名：材料导报

外文期刊名：Materials Review

收录：CSTPCD;;Scopus;北大核心:【北大核心2011】；CSCD:【CSCD2013_2014】；

基金：国家林业公益性行业科研专项(201204602)

语种：中文

中文关键词：差示扫描量热法;紫胶树脂;玻璃化转变温度(Tg)

外文关键词：differential scanning calorimetry （DSC） method; lac resin; glass transition temperature （Tg）

分类号：TQ314.1;S759.71

摘要：基于紫胶树脂的聚合物特性,玻璃化转变温度是否存在及其测定方法是紫胶树脂热性质中被长期忽视的重要命题;通过差示扫描量热（DSC）法的精细操作及直接测定,在所测得的DSC曲线上成功地观测到了碱提紫胶树脂与其他聚合物相同的比热容阶跃,并计算了此DSC曲线上比热容阶跃变化率最大处所对应的温度（Tg）,而聚合物的此阶跃均由玻璃化转变引起;进一步研究发现,当升温速率为（7±0.5）℃/min,试样量为（7.0±0.1） mg,吹扫气流量为（15±1）mL/min,试样粒径为125～250 μm,消除热历史温度为（35士0.5）℃时,测得的DSC曲线符合规则的玻璃化转变线型;在此优化条件下测得云南紫胶虫紫胶、普萨紫胶虫紫胶、仰光紫胶虫紫胶、紫胶蚧紫胶、碱提紫胶树脂、紫胶颗粒胶、紫胶片胶、NaClO漂白胶、H2 O2漂白胶的Tg值分别为22.7℃、29.8℃、30.8℃、32.9℃、34.3℃、33.9℃、28.6℃、23.3℃、16.4℃,对评价各类紫胶原胶及其树脂产品的热稳定条件具有一定的指导意义,但仍需进一步研究证实.
Based on thepolymer features of lac resin,there is an important proposition ignored for a long time that whether it has a glass transition temperature（Tg） of lac resin and how to determine it.The specific heat capacity jump of alkaline extracted lac were observed by the measurement of differential scanning calorimetry（DSC）.The temperature（Tg） corresponding to the maximum change rate of the specific heat capacity jump on the DSC curve was measured.The further research proved that the regular line style could be obtained under the conditions,that the velocity of heating the sample was（7±0.5） ℃/min,the weight of the sample was（7.0±0.1） mg,the amount of the gas flowed into the apparatus was（15±1） mL/min,the size of the sample was 125-250μm,the repetitive temperature of heating the sample was （35±0.5） ℃.Furthermore,the Tg of Kerria yunnanesis lac,Kerria pusana lac,Kerria rangoonensis lac,Kerria lacca lac,alkaline extracted lac,seed lac,flake shellac,NaClO bleached shellac,H2O2 bleached shellac were measured respectively,the value were 22.7 ℃,29.8 ℃,30.8 ℃,32.9 ℃,34.3 ℃,33.9 ℃,28.6 ℃,23.3 ℃,16.4 ℃.Such results are available to evaluate the conditon of thermal stability for various lac resins and their products,but it needs more verification with further research.