丙烯化改性纤维素纳米纤丝制备纳米刷复合物及其应用

Preparation and Application of Nano-brush Composite by Propylene-modified Cellulose Nanofibril

利用丙烯酰氯(ACL)对纤维素纳米纤丝(CNF)进行改性,得到表面带有双键基团的丙烯酸纤维素纳米纤丝(ACL-CNF),然后以ACL-CNF为主链,在自由基引发的条件下与甲基丙烯酰氧乙基三甲基氯化铵(DMC)、丙烯酰胺(AM)和2-丙烯酰胺-2-甲基丙磺酸(AMPS)进行自由基共聚以合成毛刷状复合物(PAADAC);采用傅里叶变换红外光谱(FT-IR)、固态^(13)C核磁共振(^(13)C NMR)对ACL-CNF的结构进行表征;采用透射电子显微镜(TEM)、流变仪、旋转黏度计对PAADAC结构和性能进行系统分析,并通过模拟驱替实验验证PAADAC驱油性能。结果表明,ACL-CNF的取代度随着ACL用量增加呈先增大后减小的趋势,当ACL与CNF质量比为3∶1时,ACL-CNF取代度最大,为2.31;与PAAD (无ACL-CNF)相比,PAADAC表现出较强的黏弹稳定性、耐温抗盐性;相对于水驱,PAADAC可提高原油采收率8.83个百分点。

Cellulose nanofibril(CNF)was modified by acryloyl chloride(ACL)to obtain acrylic cellulose nanofibril(ACL-CNF)with double bond group on the surface. After that,with ACL-CNF as the main chain,the brush-like complex(PAADAC)was synthesized by free radical copolymerization with methylacryloxyethyl trimethyl ammonium chloride(DMC),acrylamide(AM),2-acrylamide-2-methylpropanesulfonic acid(AMPS)as monomers under the condition of free radical activation. The structure of ACL-CNF was characterized by Fourier transform infrared spectroscopy(FT-IR)and^(13)C nuclear magnetic resonance(^(13)C NMR). Moreover,the structure and properties of PAADAC were systematically analyzed by transmission electron microscopy(TEM),rheometer,and rotary viscometer,and the oil displacement performance of PAADAC was verified by simulated displacement experiment. The results showed that the substitution degree of ACL-CNF increased first and then decreased with the increase of ACL dosage,reaching the maximum of 2. 31 at ACL to CNF mass ratio of 3∶1. Compared with PAAD(without ACL-CNF),PAADAC showed stronger viscoelastic stability,temperature resistance and salt tolerance,and improved the recovery efficiency of crude oil by 8. 83 percentage points compared with the water flooding mode.