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、yidingzhandubingjuyoulianghaokefangxingderongye,chengfangsiyuanye。yekeyoujunxiangrongyejuhezhijiededaofangsiyuanye。gaojuwuzairongjieqianxianfashengrongzhang,jirongjixianxianggaojuwuneibushenru,shidafenzizhijiandejulibuduanzengda,ranhourongjiexingchengjunyunderongye。zhenggeguochengsuoxushijianhenchang,rongzhangguochengdesududuirongjiesuduyouzhongyaoyingxiang。gaojuwurongyezaifangsizhiqian,xujinghunhe、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。 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. 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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