PVA纳米纤维自增强薄膜的制备及性能研究

Preparation and Property of PVA Nanofiber Self-Reinforced Films

通过静电纺丝法制备硼酸交联的聚乙烯醇(PVA)纳米纤维,然后与PVA水溶液复合,制备PVA纳米纤维自增强薄膜。采用扫描电子显微镜(SEM)和X-射线衍射(XRD)表征PVA纳米纤维的形貌和结晶度,采用紫外可见光谱(UV-Vis)表征自增强薄膜的透光性,采用万能材料试验机和SEM表征自增强薄膜的力学性能和微观形貌,采用热重-微热重(TG-DTG)分析和动态热机械分析(DMA)表征自增强薄膜的热稳定性和阻尼性能。结果表明:PVA纳米纤维的直径约300 nm,纤维中PVA结晶度高于纯PVA膜;与纯PVA膜相比,PVA纳米纤维含量为5%(以膜的总质量计)的自增强薄膜的透光性下降3%,断裂伸长率提高2.07倍,拉伸强度提高3.97倍;TG-DTG结果表明,自增强薄膜的热稳定性增强,热分解速度降低,主要失重阶段的最大失重速率降低0.46%·℃-1,最大失重速率时的温度提高15℃;DMA结果表明,在35~150℃区间,自增强薄膜的Tanδ值是纯PVA膜的3倍以上,显示出更为优异的阻尼性能。

We firstly prepared boric acid cross-linked polyvinyl alcohol(PVA)nanofibers by an electrospinning method,and then prepared PVA nanofiber self-reinforced films through the complex of PVA nanofibers with PVA aqueous solution.Moreover,we characterized the morphology and crystallinity of PVA nanofibers by scanning electron microscope(SEM)and X-ray diffraction(XRD),characterized the light transmittance of the self-reinforced films by UV-Vis spectroscopy(UV-Vis),characterized the mechanical properties and micro morphology of the self-reinforced films by universal testing machine and SEM,and analyzed the thermal stability and damping performance of the self-reinforced films by thermogravimetry-derivative thermogravimetry thermal(TG-DTG)analysis and dynamic thermal mechanical analysis(DMA).The results show that the diameter of PVA nanofiber is about 300 nm,and the crystallinity of PVA in the fiber is higher than that of pure PVA film.Compared with pure PVA film,the light transmittance of the self-reinforced films containing 5%(calculated by the total weight of the film)of PVA nanofiber decreases by 3%,and the elongation at break and tensile strength increase by 2.07 times and 3.97 times,respectively.The TG-DTG results show that the self-reinforced films have a higher thermal stability and a lower thermal decomposition rate,the maximum weight loss rate in the main weightlessness stage decreases by 0.46%·℃-1,and the maximum weight loss temperature increases by 15℃.The DMA results show that,in the range of 35℃to 150℃,the Tanδvalue of the self-reinforced films is more than 3 times that of pure PVA film,showing better damping performance.