废旧天丝溶解液流变及固化方式的研究

Study on Rheology and Curing Methods of Waste Tencel Dissolving Solution

为了探讨废旧天丝溶解液的流变及固化方式,采用HEC来改变废旧天丝溶解液的流变性,制备出质量分数为1%、2%、3%、4%、5%、6%和7%的七种的打印液,通过流变性能测试,得出溶液均具有剪切稀化性。通过单因素试验对打印工艺进行优化,确定优化后的打印工艺为:浆料挤出速度2.0 mm/s,针头移动速度20 mm/s,针头直径0.31 mm。采用直接墨水书写(Direct Ink Writing,简称DIW)技术将制备的七种液体进行打印,通过成形情况确定出较优浓度为4%、5%和6%。采用冷冻干燥、热固化和光固化对打印织物进行固化研究,通过收缩变形、颜色气味确定出最优浓度为6%,并优选热固化和冷冻干燥固化这两种固化方式,对其打印织物的性能进行测试和表征。结果表明,冷冻干燥织物表面有小而尖锐的凸起,截面呈现横向层状结构;热固化织物表面较大而平的突起较冷冻干燥固化方式舒适度更好,截面有均匀致密的竖向片状结构;冷冻干燥固化织物和热固化织物的红外光谱基本一致;与织物脱色前后的X射线图谱比较,两种固化方式的打印织物纤维素Ⅱ型和纤维素Ⅲ型的特征衍射峰转换成了混合晶型的特征峰,且特征峰宽而窄,衍射能力弱;两种固化方式表现出相似的热学性能。

In order to explore the rheology and curing methods of waste tencel dissolving solution,HEC was used to hange the rheological performance of the waste tencel dissolving solution,seven printing solutions with mass fractions of 1%,2%,3%,4%,5%,6% and 7% were prepared,and all the solutions had shear thinning property by rheological performance testing.The printing process was optimized by single-factor test and the optimized printing process was determined as follows:paste extrusion speed of 2.0 mm/s,needle movement speed of20 mm/s,and needle diameter of 0.31 mm.The seven prepared solutions were printed by Direct Ink Writing(DIW) technology,and the preferred concentrations were determined by forming conditions as 4%,5%,and 6%.Freeze-drying,heat-curing and light-curing methods were adopted to conduct curing study on the printed fabrics.The optimal concentration of 6% was determined by shrinkage deformation and color odor,the two curing methods of heat-curing and freeze-drying were selected,and the performance of the printed fabrics was tested and characterized.The results showed that the surface of freeze-dried fabrichad small and sharp bumps and the cross-section showed a horizontal laminar structure;the larger and flatter bumps on the surface of the heat-cured fabric were more comfortable than those of the freeze-dried curing method,and the cross-section had a uniform and dense vertical lamellar structure.The infrared spectra of the freeze-dried eured fabric and the heat-cured fabric were basic ally the same;compared with the X-ray spectrum of the fabric before and after decolorization,the characteristic diffraction peaks of cellulose type τ and cellulose type Ⅲ of the printed fabrics of two curing methods were converted into the characteristic peaks of mixed crystalline type,and the characteristic peaks were broad and narrow with weak diffraction ability;and the two curing methods showed similar thermal properties.