松香接枝纳米纤维素增强天然橡胶复合材料的制备及性能研究

Preparation and Characterization of Rosin Grafted Cellulose Nanocrystals Reinforced Natural Rubber Composites

采用松香改性纤维素纳米晶体(CNC),合成松香接枝纤维素纳米晶体(R-CNC),并以R-CNC增强天然橡胶(NR),制备松香接枝纤维素纳米晶体增强天然橡胶(R-CNC/NR)复合材料,并采用FT-IR、UV-Vis、XRD、SEM和万能试验机对R-CNC和R-CNC/NR的结构及性能进行表征。FT-IR证明R-CNC成功合成,通过UV-Vis试验得松香的接枝率为30%,XRD试验测得R-CNC/NR的结晶度为53.94%,SEM分析表明相比于CNC,R-CNC作为填料在NR分子中具有更好的相容性。通过拉伸试验表明NR拉伸强度为0.33 MPa;当CNC质量分数为40%时,纤维素纳米晶体增强天然橡胶(CNC/NR)的拉伸强度为1.56 MPa,弹性回复率88.75%;当R-CNC质量分数为40%时,R-CNC/NR的拉伸强度为2.87 MPa,弹性回复率90.04%。因此R-CNC作为填料更好的增强了NR的机械性能。

Cellulose nanocrystals(CNC)modified by rosin were used to synthesize rosin grafted cellulose nanocrystals(R-CNC).And R-CNC was applied as filler to strengthen natural rubber(NR)forming rosin grafted cellulose nanocrystals reinforced natural rubber composites(R-CNC/NR).FT-IR,UV-Vis,scanning electron microscope(SEM),X-ray diffraction(XRD)and tensile strength were employed to investigate the properties and performance.The successful grafting of rosin from CNC could be proved by FT-IR.The grafting rate of rosin calculated by UV-Vis was 30%.XRD proved that R-CNC/NR had excellent crystallinity.SEM test showed that R-CNC had better compatibility with NR.Tensile test showed that the tensile strength of NR was 0.33 MPa.When the content of CNC was 40%,the tensile strength of natural rubber reinforced by cellulose nanocrystals(CNC/NR)was 1.56 MPa and the elastic recovery value was 88.75%.When the content of R-CNC was 40%,the tensile strength of R-CNC/NR was 2.87 MPa and the elastic recovery value was 90.04%.Therefore,the reinforcing effect of R-CNC on NR was better than that of CNC.