摘要
天然橡胶(NR)加工过程中的熟化作用及后续的贮存硬化会导致橡胶烃分子链端基或异常基团与非胶组分形成交联结构产生凝胶。按照凝胶产生的3个主要阶段,可以将凝胶分为胶乳熟化凝胶、凝块熟化凝胶和贮存硬化凝胶,分别制备了含胶乳熟化凝胶的生胶(NR-L)、含凝块熟化凝胶的生胶(NR-C)和含贮存硬化凝胶的生胶(NR-S),研究了凝胶结构的形成方式与NR性能之间的联系。塑炼特性结果表明,门尼黏度和凝胶含量在塑炼时间2 min内快速下降,但NR-L的下降速率要明显慢于NR-C和NR-S,塑炼结束后也保持了更高的门尼黏度值和凝胶含量,说明凝胶网络结构的强度不同,NR-L的网络结构强度更高;氮含量方面,NR-L最高,NR-C最低,酯基含量方面,NR-L最高,NR-S最低。温度扫描应力松弛试验结果表明,NR-L的网络结构主要是由磷脂为枝化点的天然网络组成,NR-S的网络结构主要由以蛋白质为枝化点的天然网络组成。同时,以磷脂作为枝化点的天然网络强度高于以蛋白质作为枝化点的天然网络。
The curing effect and subsequent storage hardening during the processing of natural rubber(NR)will cause the end groups or abnormal groups of rubber hydrocarbon molecules to form cross-linked structures with the non-adhesive components to produce gels.According to the three main stages of gel production,the gels can be divided into latex ripening gel,clot curing gel and storage hardening gel,and raw rubber containing latex curing gel(NR-L),raw rubber containing curing gel(NR-C)and raw rubber containing storage hardening gel(NR S)were prepared.The results show that the Mooney viscosity and gel content decreas rapidly within 2 min of mastication time,but the decline rate of NR-L is significantly slower than that of NR-C and NR-S,and the Mooney viscosity and gel content are also maintained at the end point,indicating that the strength of gel network structure is different,and the strength of the network structure of NR-L is higher.In terms of nitrogen content,NR-L is the highest,NR-C is the lowest,ester content,NR-L is the highest,NR-S is the lowest,and further temperature scanning stress relaxation test results show that the network structure of NR-L is mainly composed of the natural network of phospholipids as branching point,and the network structure of NR-S is mainly composed of the natural network with protein as branching point,and the natural network strength with phospholipid as branching point is higher than that of the natural network with protein as branching point.
作者
谷丰收
张福全
林宏图
王兵兵
李高荣
廖建和
廖禄生
Fengshou Gu;Fuquan Zhang;Hongtu Lin;Bingbing Wang;Gaorong Li;Jianhe Liao;Lusheng Liao(School of Materials Science and Engineering,Hainan University,Haikou 570288,China;Agricultural Products Processing Research Institute of Chinese Academy of Tropical Agricultural Sciences,Guangdong Provincial Key Laboratory of Natural Rubber Processing,Zhanjiang 524001,China;Hainan Provincial Key Laboratory of Natural Rubber Processing,Zhanjiang 524001,China)
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2024年第9期86-91,共6页
Polymer Materials Science & Engineering
基金
国家重点研发计划(2022YFD2301203)
广东省重点领域研发计划项目(2020B020217001)
现代农业产业技术体系建设专项资金资助(CARS-33-JG2)
中央级公益性科研院所基本科研业务费专项(1630122022006)。
关键词
天然橡胶
凝胶结构
天然网络
塑炼特性
natural rubber
gel structure
natural network
mastication properties
