摘要
首先对纤维素纳米晶(CNC)分别进行80℃烘箱干燥24 h和120℃抽真空除水48 h两种预处理,然后将CNC分散到己内酰胺(CL)中并选用低碱性的乙基溴化镁作为引发剂,利用CL阴离子开环聚合制备得到单体浇铸尼龙6/CNC(MCPA6/CNC)复合材料。研究CNC不同预处理方式和添加量对复合材料性能的影响。比较复合材料中CL的转化率,发现MCPA6/CNC复合材料中CL的转化率比纯MCPA6中的低,而120℃预处理CNC能减弱CNC对CL的阻聚作用。使用差示扫描量热仪研究了复合材料的熔融结晶性能,在低添加量下,120℃预处理CNC改性的MCPA6/CNC复合材料的结晶度有所下降,但随着CNC添加量的继续增加,复合材料的结晶度呈上升趋势,结晶温度更高,半峰宽更窄,当添加120℃预处理CNC质量分数达到10%时,复合材料的结晶度从纯MCPA6的50.7%提高到53.8%,结晶温度比纯MCPA6提高量8.4℃,半峰宽从纯MCPA6的9.0℃减小到6.3℃。力学性能测试结果表明,当添加120℃预处理CNC质量分数为1%时,MCPA6/CNC复合材料的拉伸强度、弯曲强度和弯曲弹性模量分别为80.2 MPa,111.3 MPa和2.8 GPa,较纯MCPA6分别提高了2.2%,14.5%和16.7%;当添加120℃预处理CNC质量分数为10%时,复合材料的断裂伸长率提高了65.3%。
The cellulose nanocrystals(CNC)were pretreated by the oven drying at 80℃ for 24 h and vacuum dewatering at 120℃ for 48 h,then,CNC was dispersed in caprolactam(CL)and low-alkaline ethylmagnesium bromide was used as initiator to prepare monomer cast nylon 6/CNC composites(MCPA6/CNC)by CL anionic ring-opening polymerization.The influences of different pretreatment methods and addition amount of CNC on the properties of the composites were studied.It is found that the conversion rate of CL in MCPA6/CNC composite is lower than that in pure MCPA6,and the pretreatment at 120℃ can weaken the inhibitory effect of CNC on CL polymerization.The melting and crystallization properties of the composites were studied by differ-ential scanning calorimetry.The crystallinity of MCPA6/CNC composites modified by CNC at 120℃ pretreatment decreases at low addition.However,with the increase of the amount of CNC,the crystallinity shows an upward trend,with higher crystallization temperature and narrower half peak width.When the mass fraction of CNC pretreated at 120℃ reaches 10%,the crystallinity increases from 50.7% of pure MCPA6 to 53.8%,the crystallization temperature is 8.4℃higher than that of pure MCPA6,and the half peak width decreases from 9.0℃of pure MCPA6 to 6.3℃.The results of mechanical properties test show that when the mass fraction of CNC pretreated at 120℃ is 1%,the tensile strength,flexural strength and flexural elastic modulus of MCPA6/CNC composite are 80.2 MPa,111.3 MPa and 2.8 GPa which are 2.2%14.5% and 16.7% higher than that of pure MCPA6 respectively.When the mass fraction of CNC pretreated at 120℃ is 10%,the elongation at break of composite is increased by 65.3%.
作者
张电子
史豪
张晓潭
阚泽
Zhang Dianzi;Shi Hao;Zhang Xiaotan;Kan Ze(China Pingmei Shenma Energy Chemical Group Co.,Ltd.,Pingdingshan 467000,China;School of Polymer Science and Engineering,Qingdao University of Science and Technology,Qingdao 266042,China)
出处
《工程塑料应用》
CAS
CSCD
北大核心
2021年第7期1-7,共7页
Engineering Plastics Application
基金
国家自然科学基金项目(51803104)
中国博士后科学基金项目(2019M652154)。
关键词
纤维素纳米晶
尼龙6
原位聚合
复合材料
cellulose nanocrystals
nylon 6
in-situ polymerization
composite
