摘要
文中以水为增塑剂,研究了不同卡拉胶/水溶液比例制备卡拉胶膜材料的热塑加工工艺。在此基础上,分别以Ca^(2+),Na^(+)和Mg^(2+)为交联剂,研究了盐离子的种类和浓度对ι型卡拉胶膜材料结构及性能的影响。结果表明,ι型卡拉胶可以在水的作用下,在热压机中热塑加工成型,当ι型卡拉胶/水质量比为1:0.8左右时成膜效果最佳。卡拉胶膜的结构性能受材料的塑化效果和盐离子的静电协同作用共同影响。随着离子半径减小(Ca^(2+)>Na^(+)>Mg^(2+)),盐离子与水分子的水合作用增强(Ca^(2+)+^(2+)),热塑性卡拉胶的塑化效果、膜透光性和热稳定性依次降低。与未改性卡拉胶相比,盐离子改性卡拉胶材料的拉伸强度和断裂伸长率均有所提高,说明盐离子的静电作用可以增加卡拉胶分子链之间的缠结,提高其力学性能;对比3种盐离子,Ca^(2+)浓度在0~50μL范围内,改性卡拉胶的拉伸强度和断裂伸长率由原来的4.94 MPa和6.4%分别提高到了10.18 MPa和9.2%;由于Ca^(2+)与水分子水合作用较弱及二价离子具有更强的静电作用,其改性卡拉胶材料的力学性能与其它2种盐离子相比效果更佳。
Water and salt ion(Ca^(2+),Na^(+)and Mg^(2+))solutions were respectively used as plasticizer and crosslinking agent to prepare thermoplasticι-carrageenan films.The effects of type and concentration of salt ions on the structure and properties of carrageen films were studied.The experimental results show that carrageenan can be thermoplastic processed in hot press under the action of water,and the optimal mass ratio of carrageenan/water is about 1:0.8.The structure and properties of carrageen film are influenced by the plasticizing effect of processing and electrostatic synergy of salt ions.As the ionic radius decreases(Ca^(2+)>Na^(+)>Mg^(2+)),the hydration of salt ion is enhanced(Ca^(2+)<Na^(+)<Mg^(2+)),the plasticizing effect,film light transmittance and thermal stability of thermoplastic carrageenan decrease successively.Compared with unmodified carrageenan film,the fracture strength and elongation at break of carrageenan modified with salt ions are improved,which indicates that the electrostatic action of salt ions can increase the entanglement between the molecular chains of carrageenan and improve its mechanical properties.Compared with the three salt ions,the tensile strength and elongation at break of Ca^(2+)modified carrageenan increase from 4.94 MPa and 6.4%to 10.18 MPa and 9.2%,respectively.Due to the lower hydration of Ca^(2+)and higher electrostatic action of the bivalent ions,the mechanical properties of carrageenan materials are better than those of the other two salt ions.
作者
陈康
罗子木
孙桂林
张宇
Kang Chen;Zimu Luo;Guilin Sun;Yu Zhang(College of Chemistry and Life Science,Hubei University of Education,Wuhan 430205,China;CGN Topu(Hubei)New Materials Co.,LTD.,Hanchuan 431615,China)
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2024年第5期31-38,共8页
Polymer Materials Science & Engineering
基金
国家自然科学基金资助项目(51903077)。
关键词
ι型卡拉胶
盐离子溶液
热塑性
力学性能
ι-carrageenan
salt ion solution
thermoplasticity
mechanical property
