濕法無紡布:shijiangzhiyushuijiezhizhongdexianweiyuanliaokaisongchengdanxianwei,tongshishibutongxianweiyuanliaohunhe,zhichengxianweixuanfujiang,xuanfujiangshusongdaochengwangjigou,xianweizaishitaixiachengwangzaijiaguchengbu。
濕法紡絲 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)、過(guo)濾(lv)和(he)脫(tuo)泡(pao)等(deng)紡(fang)前(qian)準(zhun)備(bei)工(gong)序(xu),以(yi)使(shi)紡(fang)絲(si)原(yuan)液(ye)的(de)性(xing)質(zhi)均(jun)勻(yun)一(yi)致(zhi),除(chu)去(qu)其(qi)中(zhong)所(suo)夾(jia)帶(dai)的(de)凝(ning)膠(jiao)塊(kuai)和(he)雜(za)質(zhi)並(bing)脫(tuo)除(chu)液(ye)中(zhong)的(de)氣(qi)泡(pao)。在(zai)粘(zhan)膠(jiao)纖(xian)維(wei)生(sheng)產(chan)中(zhong),紡(fang)前(qian)準(zhun)備(bei)還(hai)包(bao)括(kuo)熟(shu)成(cheng)工(gong)序(xu),使(shi)粘(zhan)膠(jiao)具(ju)有(you)必(bi)要(yao)的(de)可(ke)紡(fang)性(xing)。 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。 在(zai)第(di)一(yi)導(dao)絲(si)盤(pan)的(de)拉(la)伸(shen)力(li)作(zuo)用(yong)下(xia),擠(ji)出(chu)細(xi)流(liu)在(zai)越(yue)過(guo)最(zui)大(da)直(zhi)徑(jing)後(hou)逐(zhu)漸(jian)變(bian)細(xi),細(xi)化(hua)過(guo)程(cheng)一(yi)直(zhi)持(chi)續(xu)到(dao)原(yuan)液(ye)細(xi)流(liu)完(wan)全(quan)固(gu)化(hua)為(wei)止(zhi)。濕(shi)紡(fang)中(zhong)細(xi)流(liu)直(zhi)徑(jing)的(de)變(bian)化(hua)不(bu)僅(jin)是(shi)拉(la)伸(shen)形(xing)變(bian)的(de)結(jie)果(guo),而(er)且(qie)還(hai)與(yu)質(zhi)量(liang)傳(chuan)遞(di)過(guo)程(cheng)有(you)關(guan)。從(cong)噴(pen)絲(si)頭(tou)到(dao)固(gu)化(hua)點(dian)的(de)一(yi)段(duan)紡(fang)程(cheng)為(wei)纖(xian)維(wei)成(cheng)形(xing)區(qu),是(shi)纖(xian)維(wei)結(jie)構(gou)形(xing)成(cheng)的(de)關(guan)鍵(jian)區(qu)域(yu)。 shifangchushengxianweiyouyuhanyoudaliangyetierchuyurongzhangzhuangtai。dafenzijuyouhendadehuodongxing,erqiequxiangduhendi,qixingtaijiegouyufangsigongyitiaojianguanxijiweimiqie。xuanzehekongzhifangsigongyitiaojian,kezhidebutonghengjiemianxingzhuanghuoteshumaoxikongjiegouheteshuxingnengdexianwei。 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. shifachangsifangsijidejuanraozhuangzhiyoulixinguanshihuotongguanshi。fangzhiduanxianweishitongchangcaiyongfangsihouchulilianheji,gefangsibuweichengxinghoudechushengxianweibeijihechengshu,lianxujinxinghouchuli。 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。
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