《植物纤维形态对纸张性能的影响课件》由会员分享,可在线阅读,更多相关《植物纤维形态对纸张性能的影响课件(38页珍藏版)》请在金锄头文库上搜索。
1、Chapter 1 The Composition and Structure of Wood1 Tianjin University of Science & Technology第五节第五节 植物纤维形态对纸张性能的影响植物纤维形态对纸张性能的影响( (一一) )常见原料的细胞组成比较常见原料的细胞组成比较 针叶材:管胞、木射线管胞和木射线薄壁细胞;针叶材:管胞、木射线管胞和木射线薄壁细胞; 阔阔叶叶材材:木木纤纤维维、管管胞胞、导导管管、薄薄壁壁细细胞胞及及木木射射线薄壁细胞;线薄壁细胞; 禾本科:纤维细胞、杂细胞禾本科:纤维细胞、杂细胞( (表皮细胞、石细胞表皮细胞、石细胞) )。Ch
2、apter 1 The Composition and Structure of Wood2 Tianjin University of Science & Technology多数杂细胞由于腔大、壁薄、长度短,制浆时会吸收大多数杂细胞由于腔大、壁薄、长度短,制浆时会吸收大量蒸煮药液;量蒸煮药液;洗浆时会堵塞洗浆时会堵塞洗浆机洗鼓洗浆机洗鼓的网孔,降低洗涤能力;成纸的网孔,降低洗涤能力;成纸强度低;强度低;表皮细胞在碱法制浆中会增加废液的硅含量,在酸法制表皮细胞在碱法制浆中会增加废液的硅含量,在酸法制浆中则成片状存在、增加浆中则成片状存在、增加纸病纸病。原料的杂细胞含量越高,其制浆造纸价值就越
3、低。原料的杂细胞含量越高,其制浆造纸价值就越低。制浆造纸价值:制浆造纸价值:棉花及麻类棉花及麻类针叶材原料针叶材原料阔叶材原料阔叶材原料禾本科原料。禾本科原料。 杂细胞对制浆造纸的影响杂细胞对制浆造纸的影响Chapter 1 The Composition and Structure of Wood3 Tianjin University of Science & Technology( (二二) )纤维形态及其与纸张性质的关系纤维形态及其与纸张性质的关系纤纤维维形形态态包包括括纤纤维维的的长长度度、宽宽度度、壁壁厚厚、腔腔径径等等基基本本形形态态指指标标外外,还还包包括括长长宽宽比比、壁腔比
4、以及纤维的粗度壁腔比以及纤维的粗度等。等。Chapter 1 The Composition and Structure of Wood4 Tianjin University of Science & Technology nni i L Li i数量平均长度数量平均长度 = = n ni i nni i L Li i2 2质量平均长度质量平均长度 nni i L Li i n ni i L Li i3 3二重质均纤维长二重质均纤维长 = = n ni i L Li i2 2n ni : i : 某级分中纤维数目;某级分中纤维数目;L Li i: 某级分中纤维平均长。某级分中纤维平均长。1
5、1纤维的长度(书纤维的长度(书3838页)页)Chapter 1 The Composition and Structure of Wood5 Tianjin University of Science & Technology2 2纤维形态的频率分布纤维形态的频率分布 n n分布频率分布频率 X 100(%) X 100(%) n n将纤维按不同长度(或宽度)的大小分级,计算将纤维按不同长度(或宽度)的大小分级,计算每一级分纤维根数占纤维总数量的百分比例,可每一级分纤维根数占纤维总数量的百分比例,可得数量分布频率或质量分布频率。得数量分布频率或质量分布频率。Chapter 1 The Com
6、position and Structure of Wood6 Tianjin University of Science & TechnologyChapter 1 The Composition and Structure of Wood7 Tianjin University of Science & Technology( (二二) )纤维形态及其与纸张性质的关系纤维形态及其与纸张性质的关系 纤维长度纤维长度 1 1长宽比长宽比= -= - 纤维宽度纤维宽度长宽比大的纤维,成纸时单位面积中纤维之间相互长宽比大的纤维,成纸时单位面积中纤维之间相互交织的次数多,纤维分布细密,成纸强度高,交
7、织的次数多,纤维分布细密,成纸强度高,特别是特别是撕撕裂度、裂断长、耐折度裂度、裂断长、耐折度等强度指标等强度指标。(书。(书39页表页表1-19)一般认为长宽比小于一般认为长宽比小于45的原料,应用价值很低。的原料,应用价值很低。Chapter 1 The Composition and Structure of Wood8 Tianjin University of Science & Technology2 2壁腔比壁腔比 2 X 2 X 细胞单壁厚度细胞单壁厚度 壁腔比壁腔比 = = 细胞腔直径细胞腔直径Cell wall thicknessWidthChapter 1 The Com
8、position and Structure of Wood9 Tianjin University of Science & Technology 2 X 2 X 细胞单壁厚度细胞单壁厚度刚性系数刚性系数 = = X100 X100 纤维直径纤维直径 细胞腔直径细胞腔直径柔性系数柔性系数 = = X100 X100 纤维直径纤维直径Chapter 1 The Composition and Structure of Wood10 Tianjin University of Science & Technology纤维的壁腔比不同,则它们的柔软程度不同。壁腔纤维的壁腔比不同,则它们的柔软程度不
9、同。壁腔比小(即纤维的柔软性好)的纤维,成纸时纤维间的接比小(即纤维的柔软性好)的纤维,成纸时纤维间的接触面积较大,故结合力强,成纸的强度高;反之,壁腔触面积较大,故结合力强,成纸的强度高;反之,壁腔比大的纤维则较僵硬,成纸时纤维间的接触面积较小,比大的纤维则较僵硬,成纸时纤维间的接触面积较小,结合力小,成纸的强度差。结合力小,成纸的强度差。Chapter 1 The Composition and Structure of Wood11 Tianjin University of Science & Technology 壁腔比壁腔比1 1 1 为劣等原料。为劣等原料。Chapter 1 T
10、he Composition and Structure of Wood12 Tianjin University of Science & Technology图:理想的纤维结构图:理想的纤维结构厚壁纤维厚壁纤维A A与薄壁纤与薄壁纤维比较。维比较。制浆造纸工程大全制浆造纸工程大全P19P19Chapter 1 The Composition and Structure of Wood13 Tianjin University of Science & TechnologyPaper on Close Examination Chapter 1 The Composition and Str
11、ucture of Wood14 Tianjin University of Science & Technology3 3纤维的粗度纤维的粗度(Coarseness)(Coarseness)每每 100m100m长长 度度 的的 绝绝 干干 纤纤 维维 的的 质质 量量 (mg)(mg), 用用decigrex(dg)decigrex(dg)表示。表示。W=30CWT=5W=40CWT=5W=30CWT=10W=40CWT=10Increasing Coarseness mg/mRelative amount of material in fibreChapter 1 The Composi
12、tion and Structure of Wood15 Tianjin University of Science & Technology纤维粗度大于纤维粗度大于30dg30dg的纸浆,造纸的纸页较的纸浆,造纸的纸页较粗糙,平滑度低;小于粗糙,平滑度低;小于10dg10dg者,纸页细腻,者,纸页细腻,平滑度好,但是裂断长、耐破度、撕裂度平滑度好,但是裂断长、耐破度、撕裂度及耐折度下降。及耐折度下降。Chapter 1 The Composition and Structure of Wood16 Tianjin University of Science & Technology4. 4.
13、 纤维的卷曲因子(纤维的卷曲因子(Form factor Form factor 或或 Curl IndexCurl Index)D L Form factor = D/LCurl Index = L/D - 1Chapter 1 The Composition and Structure of Wood17 Tianjin University of Science & Technology6. 6. 扭结指数(扭结指数(Kink index Kink index )Measurement of anglesReported according to Kibblewhites kink in
14、dex formulaChapter 1 The Composition and Structure of Wood18 Tianjin University of Science & TechnologyPrinciple of mechanical refining. Wood chips are fed into the refining zone where they are disintegrated between two grooved discs of which at least one is revolving.纤维的扭结纤维的扭结是指由于纤是指由于纤维细胞壁受维细胞壁受损
15、而产生的损而产生的突然而生硬突然而生硬的转折。的转折。Chapter 1 The Composition and Structure of Wood19 Tianjin University of Science & Technology扭结指数可用单位长度上扭结平均个数(个扭结指数可用单位长度上扭结平均个数(个/mm)或单根纤维上扭结平均个数(个或单根纤维上扭结平均个数(个/单根纤维)表示。单根纤维)表示。Chapter 1 The Composition and Structure of Wood20 Tianjin University of Science & Technology定义
16、:定义:1)造纸原料中长度等于或小于0.2mm的纤维2)造纸原料中通过纤维筛分仪的200目筛(0.074mm)的纤维来源:来源:1)初级细小纤维:木材中原有的小颗粒,如切断的纤维、导管分子、纹孔、射线细胞和薄壁组织细胞(量少);2)二次细小纤维:浆料在生产和后续的抄造过程中通过机械处理产生的纤维壁碎片(量多)。6.6.细小纤维(细小纤维(fines)fines)Chapter 1 The Composition and Structure of Wood21 Tianjin University of Science & Technology影响影响1)纸机的运行过程,比如留着、滤水、白水回收
17、系统、助剂效用、干燥速度等;2)纸张的性能,比如纸张结构、物理强度性能、光学性能、印刷性能等。Chapter 1 The Composition and Structure of Wood22 Tianjin University of Science & Technology( (三三) )纤维形态测定纤维形态测定1 1纤维的长、宽度测定纤维的长、宽度测定台式投影仪进行;台式投影仪进行;Kajaani FS Kajaani FS (100/200/300100/200/300)型纤维质量自动测量仪;)型纤维质量自动测量仪;纤维质量分析仪(纤维质量分析仪(FQAFQA)FibermasterF
18、ibermaster/Fibertester/FibertesterChapter 1 The Composition and Structure of Wood23 Tianjin University of Science & TechnologyChapter 1 The Composition and Structure of Wood24 Tianjin University of Science & TechnologyChapter 1 The Composition and Structure of Wood25 Tianjin University of Science &
19、TechnologyKajaani 100Kajaani 100纤维分析仪工作原理图纤维分析仪工作原理图Chapter 1 The Composition and Structure of Wood26 Tianjin University of Science & TechnologyKajaani300Chapter 1 The Composition and Structure of Wood27 Tianjin University of Science & TechnologyOptics ModuleSample outCapillarySample inFibre detecto
20、rDetector light source (Laser)PolarizersMeasurement (CCD-camera)Measurement light source LEDOptics bodySampleloop样品回路样品回路漏斗漏斗毛细管毛细管排出排出Detectionloop检测回路检测回路激光激光1 1stst 偏振器偏振器毛细管毛细管2 2ndnd 偏振器偏振器纤维检测器纤维检测器 Measurementloop测量回路测量回路发光二极管发光二极管毛细管毛细管CCD CCD 照相机照相机MeasurementMeasurement测量测量Chapter 1 The Co
21、mposition and Structure of Wood28 Tianjin University of Science & TechnologyFibermasterChapter 1 The Composition and Structure of Wood29 Tianjin University of Science & TechnologyFibertesterChapter 1 The Composition and Structure of Wood30 Tianjin University of Science & TechnologyFiberQualityAnalys
22、isOpTest Equipment Inc.Hawkesbury, ON CanadaChapter 1 The Composition and Structure of Wood31 Tianjin University of Science & TechnologyValues Measured By The Laboratory FQAValues Measured By The Laboratory FQA Fiber Length Fiber Length Fiber Length Fiber Length Fiber Width Fiber Width Fiber Width F
23、iber Width Fiber Curl Fiber Curl Fiber Curl Fiber Curl Fiber Kink Fiber Kink Fiber Kink Fiber Kink % Fines % Fines % Fines % Fines Coarseness Coarseness Coarseness Coarseness HWD/SWD Ratio HWD/SWD Ratio HWD/SWD Ratio HWD/SWD Ratio Shives Shives Shives Shives Chapter 1 The Composition and Structure o
24、f Wood32 Tianjin University of Science & Technology(四)纤维粗度和细胞壁厚对纸张性能的影响Chapter 1 The Composition and Structure of Wood33 Tianjin University of Science & TechnologyWetFiberFlexibilityPaavilainen,L.,Importanceofcoarsenessandfiberlengthinpapermaking.TappiInternationalProcessandProductQualityConference,
25、10/1988.pp.99-109.Chapter 1 The Composition and Structure of Wood34 Tianjin University of Science & TechnologyApparentSheetDensityPaavilainen,L.,Importanceofcoarsenessandfiberlengthinpapermaking.TappiInternationalProcessandProductQualityConference,10/1988.pp.99-109.Chapter 1 The Composition and Stru
26、cture of Wood35 Tianjin University of Science & TechnologyTensilestrengthPaavilainen,L.,Importanceofcrossdimensionalfiberpropertiesandcoarsenessforthecharacterizationofsoftwoodsulphatepulp.PaperijaPuuvol.75,5(1993),pp.343-351.Chapter 1 The Composition and Structure of Wood36 Tianjin University of Sc
27、ience & TechnologyWetFiberFlexibilityPaavilainen,L.,Wetfiberflexibilityandcollapsibilityofsoftwoodpulpfibres.PaperijaPuu75(1993)9-10,pp.689-702.Chapter 1 The Composition and Structure of Wood37 Tianjin University of Science & TechnologySurma-Slusarska,B.,Surewitz,W.,Theeffectofchemicalcompositionand
28、anatomicalstructureofwoodontheyieldandpropertiesofkraftpulps. CelluloseChemistryTechnology,15,1981,pp.77-97.ApparentSheetDensityChapter 1 The Composition and Structure of Wood38 Tianjin University of Science & TechnologyPaavilainen, L., Influence of morphological properties of wood fibres on sulphate pulp fiber and paper properties. Proceedings of International Paper Physics Conference held in Kona, Hawaii, 9/1991, p. 383 - 395.Tensilestrength