【作者】 曹秀军；

【导师】 陈港；

【作者基本信息】 华南理工大学 ， 制浆造纸工程， 2010， 硕士

【摘要】 随着人们环境保护意识的不断增强,可降解材料的开发已经成为材料领域二十一世纪的研究热点。如果造纸时使用一定比例的可降解纤维,同时也不降低纸张的其它性能指标,这就使得纸张不但可以满足日常的使用要求,而且在使用后可以自然降解,不会对环境构成威胁。本研究旨在为这两种可降解纤维在造纸工业尤其是新型纸张中的应用提供指导。本文对聚乳酸纤维和海藻纤维的打浆及抄造性能进行了研究,探讨了浆料配比、压光和热处理对聚乳酸纤维配抄纸和海藻纤维配抄纸性能的影响;研究了用热重分析法和萃取抽提法测定配抄纸中聚乳酸纤维和海藻纤维留着率的可行性;用埋土法和紫外老化法对聚乳酸纤维配抄纸和海藻纤维配抄纸的降解性能进行了研究。结果显示:1.随着打浆时间的增加,PLA浆料的打浆度变化不大,打浆12h后其打浆度为11°SR;打浆处理对聚乳酸纤维聚集态结构的影响不大;经过打浆处理后,聚乳酸纤维的长度变短,粗度增加,纤维弯曲变形,粗细不均匀,表面变得粗糙不平,但是没有明显的分丝帚化现象;打浆处理能够提高PLA浆料的保水值,改善其亲水性能;PLA浆料与木浆配抄,随着PLA配比的增加,浆料的滤水性能得到改善。2.聚乳酸纤维配抄纸制备的较佳工艺为:PLA浆料与木浆配比为15:85,压光压力4MPa,热处理温度170℃,热处理时间2min。纸张定量60g·m-2 ,紧度0.88g·cm-3,抗张指数63.1N·m·g-1,撕裂指数5.94mN·m2·g-1,耐折度62次,湿抗张强度0.531kN·m-1,透气度110mL·min-1,不透明度67.4%,Cobb值(60s)为31.1g·m-2,PPS值为3.84μm.;聚乳酸纤维开始热失重的温度为240℃,失重量为98.67%;在154℃时开始发生熔融。3.在本实验中不能采用热重分析法测定配抄纸中聚乳酸纤维的留着率;可以采用萃取抽提法测定配抄纸中聚乳酸纤维的留着率,测得的聚乳酸纤维的留着率大于99%,留着效果比较好。4.海藻纤维表面光滑,纤维直长,亲水性能较好;保水值和结晶度比较小,分别为35.49%和9.57%;海藻纤维与木浆配抄,随着海藻纤维配比的增加,浆料的滤水性能得到改善;海藻纤维开始热失重的温度为210℃,失重量为70.71%;海藻纤维配抄纸制备实验中最佳压光压力为6MPa;热处理前后,海藻纤维配抄纸的各项性能变化都不大;在本实验中不能采用热重分析法测定配抄纸中海藻纤维的留着率。5.埋土60天后,聚乳酸纤维配抄纸和海藻纤维配抄纸都破损严重,不再具有完整的形态;纸页发黄变色,表面有霉斑产生;纸样老化降解严重,质量减少,强度下降;随着紫外老化时间的增加,聚乳酸纤维配抄纸和海藻纤维配抄纸的抗张指数、撕裂指数和耐折度都逐渐减小,透气度和不透明度逐渐增大。更多还原

【Abstract】 As the improvement of people’s sense of environment protection, the research ofbiodegradable material has been an important subject. If use a certain percentage ofbiodegradable fibers when making paper, and make sure paper’s other performance is good,the paper can not onlymeet the dailyuse requirements, but also degrade naturally, makingnoenvironment pollution. This paper is to provide guidance for the application of these twobiodegradablefibersinthepaper-makingindustry.The beating and papermaking behaviors of PLA fiber and alginate fiber were studied,and the influence of the ratio of PLA fiber and alginate fiber and press polish and hottreatment to the paper properties were researched. The retention of PLA fiber and alginatefiber in the paper was studied by means of TG and extraction. The degradation of the paperwas studied by putting the paper in the soil and Accelerated Weathering Tester for a certaintime.Theresultsindicatedthat:1.Thebeatingdegreeandthecrystallinity didn’tchangeobviouslyasbeatingtimeincreased.Thedegreewas11°SRafter12hours.Afterbeating,thefiberbecameshorter,wider,curvedandcoarse,buthadnoobviousfibrillation.AndbeatingcouldimprovethehydrophilicityofPLAfiber.Atthesametime,thebiggerPLAfiberpercentage,thebetterpulpdrainability.2. The appropriate technology of PLApaper was as follows: the ratio of PLA pulp andwood pulp was 15:85,the press polish pressure was 4MPa, the hot treatment temperature was170℃and time was 2min. The paper’s basis weight was 60g·m-2, the densitywas 0.88g·cm-3,the tensile index was 63.1N·m·g-1, the tear index was5.94mN·m2·g-1, the foldingstrength was62, the wet tensile index was 0.531kN·m-1, the porosity was 110mL·min-1, the opacity was67.4%,theCobbvalue(60s)was 31.1g·m-2,thePPSvaluewas3.84μm.ThePLAfiberstartedto lose weight at 240℃, and the weight loss was 98.67%. The PLA fiber started to melt at154℃.3.Theretentionof PLA fiberinthepapercouldnot bemeasuredbythemeanofTG, butcouldbemeasuredbythe meanofextraction,theretentionwashigherthan99%.4. The alginate fiber was smooth, straight and long. Its hydrophilicity was good. Thewater retention value was 35.49% and the crystallinity was 9.67%. The bigger alginate fiberpercentage,thebetterpulpdrainability.ThePLAfiberstartedtoloseweightat210℃,andtheweight loss was 70.71%. The appropriate press polish pressure was 6MPa. The paper properties didn’t change too much after the hot treatment. And retention of alginate fiber inthepapercouldnotbemeasuredbythe meanofTG.5. After putted in the soil for 60 days, the papers were damaged and mildewed, andbecame yellow. As the UV aging time increased, the tensile index, the tear index and thefoldingstrengthofthepaperweredecreased,buttheporosityandopacitywereincreased.更多还原