濕法無紡布:shijiangzhiyushuijiezhizhongdexianweiyuanliaokaisongchengdanxianwei,tongshishibutongxianweiyuanliaohunhe,zhichengxianweixuanfujiang,xuanfujiangshusongdaochengwangjigou,xianweizaishitaixiachengwangzaijiaguchengbu。
濕法紡絲 wet spinning 化學纖維主要紡絲方法之一,簡稱濕紡。濕紡包括的工序是: (1)製備紡絲原液; (2)將原液從噴絲孔壓出形成細流; (3)原液細流凝固成初生纖維; (4)初生纖維卷裝或直接進行後處理。
將成纖高聚物溶解在適當的溶劑中,得到一定組成、一yi定ding粘zhan度du並bing具ju有you良liang好hao可ke紡fang性xing的de溶rong液ye,稱cheng紡fang絲si原yuan液ye。也ye可ke由you均jun相xiang溶rong液ye聚ju合he直zhi接jie得de到dao紡fang絲si原yuan液ye。高gao聚ju物wu在zai溶rong解jie前qian先xian發fa生sheng溶rong脹zhang,即ji溶rong劑ji先xian向xiang高gao聚ju物wu內nei部bu滲shen入ru,使shi大da分fen子zi之zhi間jian的de距ju離li不bu斷duan增zeng大da,然ran後hou溶rong解jie形xing成cheng均jun勻yun的de溶rong液ye。整zheng個ge過guo程cheng所suo需xu時shi間jian很hen長chang,溶rong脹zhang過guo程cheng的de速su度du對dui溶rong解jie速su度du有you重zhong要yao影ying響xiang。高gao聚ju物wu溶rong液ye在zai紡fang絲si之zhi前qian,須xu經jing混hun和he、guolvhetuopaodengfangqianzhunbeigongxu,yishifangsiyuanyedexingzhijunyunyizhi,chuquqizhongsuojiadaideningjiaokuaihezazhibingtuochuyezhongdeqipao。zaizhanjiaoxianweishengchanzhong,fangqianzhunbeihaibaokuoshuchenggongxu,shizhanjiaojuyoubiyaodekefangxing。
紡絲原液被循環管道送至紡絲機,通過計量泵計量,然後經燭形濾器、連接管而進入噴絲頭(帽)。噴絲頭一般采用黃金與鉑的合金或鉭合金材料製成。在噴絲頭上有規律地分布若幹孔眼,孔徑為0.05~0.08毫hao米mi。從cong噴pen絲si孔kong眼yan中zhong壓ya出chu的de原yuan液ye細xi流liu進jin入ru凝ning固gu浴yu,原yuan液ye細xi流liu中zhong的de溶rong劑ji向xiang凝ning固gu浴yu擴kuo散san,凝ning固gu劑ji向xiang細xi流liu滲shen透tou,從cong而er使shi原yuan液ye細xi流liu達da到dao臨lin界jie濃nong度du,在zai凝ning固gu浴yu中zhong析xi出chu而er形xing成cheng纖xian維wei。濕shi紡fang中zhong的de擴kuo散san和he凝ning固gu是shi物wu理li化hua學xue過guo程cheng,但dan某mou些xie化hua學xue纖xian維wei在zai濕shi紡fang過guo程cheng中zhong還hai同tong時shi發fa生sheng化hua學xue變bian化hua。例li如ru粘zhan膠jiao纖xian維wei,纖xian維wei素su黃huang酸suan納na分fen解jie成cheng為wei纖xian維wei素su再zai生sheng纖xian維wei。
濕法紡絲速度(指卷取初生纖維的第一導絲盤速度)youyushourongjiheninggujishuangkuosansuduheningguyudeliutizulidengxianzhi,yinciyuanbirongfangsuduweidi。diyidaosipandexiansuduyufangsiyuanyedejichusuduzhibichengweipensitoulashenbi。shifanglashenbiyibanweifuzhi、零,或是很小的正值,目的是提高成形過程的穩定性。
紡絲原液是兼具粘性和彈性的彈粘體。原液從噴絲孔壓出時,有孔口脹大效應(巴勒斯效應),使擠出細流的直徑大於噴絲孔孔徑。濕紡過程中,脹大比一般為1~2。
zaidiyidaosipandelashenlizuoyongxia,jichuxiliuzaiyueguozuidazhijinghouzhujianbianxi,xihuaguochengyizhichixudaoyuanyexiliuwanquanguhuaweizhi。shifangzhongxiliuzhijingdebianhuabujinshilashenxingbiandejieguo,erqiehaiyuzhiliangchuandiguochengyouguan。congpensitoudaoguhuadiandeyiduanfangchengweixianweichengxingqu,shixianweijiegouxingchengdeguanjianquyu。
濕shi紡fang初chu生sheng纖xian維wei由you於yu含han有you大da量liang液ye體ti而er處chu於yu溶rong脹zhang狀zhuang態tai。大da分fen子zi具ju有you很hen大da的de活huo動dong性xing,而er且qie取qu向xiang度du很hen低di,其qi形xing態tai結jie構gou與yu紡fang絲si工gong藝yi條tiao件jian關guan係xi極ji為wei密mi切qie。選xuan擇ze和he控kong製zhi紡fang絲si工gong藝yi條tiao件jian,可ke製zhi得de不bu同tong橫heng截jie麵mian形xing狀zhuang或huo特te殊shu毛mao細xi孔kong結jie構gou和he特te殊shu性xing能neng的de纖xian維wei。 濕紡有各種不同的成形方式,紡絲機也有各種不同的結構。例如有單浴法或雙浴法,有深浴法或淺浴法,有漏鬥成形或管中成形等.
濕shi法fa長chang絲si紡fang絲si機ji的de卷juan繞rao裝zhuang置zhi有you離li心xin罐guan式shi或huo筒tong管guan式shi。紡fang製zhi短duan纖xian維wei時shi通tong常chang采cai用yong紡fang絲si後hou處chu理li聯lian合he機ji,各ge紡fang絲si部bu位wei成cheng形xing後hou的de初chu生sheng纖xian維wei被bei集ji合he成cheng束shu,連lian續xu進jin行xing後hou處chu理li。
濕紡不僅需要種類繁多、體積龐大的原液製備和紡前準備設備,而且還要有凝固浴、循環及回收設備,其工藝流程複雜、廠房建築和設備投資費用大、紡fang絲si速su度du低di,因yin此ci成cheng本ben較jiao高gao。製zhi造zao切qie段duan纖xian維wei時shi可ke采cai用yong數shu萬wan孔kong的de噴pen絲si頭tou或huo集ji裝zhuang噴pen絲si頭tou來lai提ti高gao生sheng產chan能neng力li。一yi般ban隻zhi有you不bu能neng用yong熔rong體ti紡fang絲si的de合he成cheng纖xian維wei,例li如ru聚ju丙bing烯xi腈jing纖xian維wei和he聚ju乙yi烯xi醇chun纖xian維wei,才cai適shi於yu用yong高gao聚ju物wu溶rong液ye濕shi紡fang生sheng產chan切qie段duan纖xian維wei和he長chang絲si束shu。 |