海鞘纤维素纳米晶对纸张性能的影响

Effect of tunicate cellulose nanocrystals on paper properties

以海鞘纤维素纳米晶(tCNC)作为增强剂,研究其对漂白化学浆纸张强度的影响。首先通过漂白法和酸水解法制备tCNC,并通过傅里叶变换红外光谱(FTIR)、透射电子显微镜(TEM)、X-射线衍射(XRD)以及马尔文粒度仪对tCNC的结构、形态、结晶度、粒径和电动电位等进行表征。然后,将浓度为10%的漂白化学浆用磨浆机打浆,得到42°SR纸浆,并抄造60 g·m^(-2)的手抄纸。在纸张抄造过程中,分别添加质量分数为0.3%、0.6%、0.9%、1.2%、1.5%的tCNC,并采用阳离子聚丙烯酰胺(CPAM)作为纳米纤维素的助留剂,同时设置空白对照组试验。考察tCNC的添加量对纸张的撕裂性能、抗张性能、耐破性能、透气度和光学性能的影响。结果显示,当tCNC的添加量为0.6%时,纸张撕裂指数最大增加12.00%;当tCNC的添加量为0.6%时,抗张指数达到最大值,与纯纸浆抄造的纸张相比,抗张指数提升了12.04%,耐破指数提升了16.55%。本试验首次使用来源于被囊动物的tCNC作为纸张的增强剂,开拓了tCNC在增强纸张强度性能上的应用范围。

In this study,tunicate cellulose nanocrystals(tCNC)were investigated as a filler added to bleached kraft pulp.First,tCNC were prepared through bleaching and acid hydrolysis.The structure,morphology,crystallinity,and particle size and zeta potential of the tCNC were characterized by Fourier transform infrared spectroscopy(FTIR),scanning electron microscopy(SEM),X-ray diffraction(XRD),and a malvern particle sizer,respectively.Second,kraft pulp with a consistency of 10%was refined to 42°SR through a PFI refiner.Then 60 g·m^(-2) handsheets were prepared from this pulp.Prior to preparing the handsheets,tunicate nanocellulose was thoroughly mixed into the pulp at four gradients:0.3%,0.6%,0.9%,1.2%,and 1.5%.Cationic polyacrylamides(CPAM)were added to the pulp slurry as a retention agent.A control experiment was set up accordingly.The effects of tCNC addition on the tearing,tensile,burst,air permeability,and optical properties of the handsheets were evaluated.The results indicated that the maximum increase in the tear index was 12.00%when tCNC was added 0.6%.The tensile index reached its maximum value when tCNC was added at 0.6%,with an increase of 12.04%compared to pure pulp sheets.The tensile index increased by 16.55%.In this experiment,nanocellulose prepared from a mantle sea animal was used for the first time as reinforcing filler in papermaking,which has greatly extended the application of tCNC in the enhancement of paper strength.