在紡織工業中,許多染整助劑經常使用的是表面活性劑的復配物。而表面活性劑復配后產生了協同效應和增效作用,出現了單一表面活性劑所沒有的功能。因此表面活性劑的復配技術與增效作用,以及復配后的表面特性與應用性質之間的關系,已成為印染助劑領域中的(de)重(zhong)(zhong)要(yao)(yao)研(yan)究(jiu)方向,亦是提高(gao)印(yin)染(ran)質量的(de)極(ji)其(qi)重(zhong)(zhong)要(yao)(yao)研(yan)究(jiu)內容。目前我國(guo)印(yin)染(ran)助劑的(de)質量與國(guo)外(wai)商品存在著較大差距,除了品種單(dan)調(diao),性(xing)能(neng)不完善(shan),開發能(neng)力不足外(wai),對表面活性(xing)劑復配原理(li)(li)及其(qi)與應用(yong)(yong)性(xing)能(neng)之(zhi)間(jian)關系研(yan)究(jiu)甚少,極(ji)待加強,為產品的(de)開發和應用(yong)(yong)提供更多的(de)理(li)(li)論指導。
由于(yu)織物精(jing)煉是在(zai)一(yi)定(ding)濃(nong)度(du)的(de)燒堿溶(rong)液(ye)中進行,而(er)NaOH溶(rong)液(ye)的(de)表(biao)面(mian)(mian)(mian)張力(li)很高(gao),很難滲透(tou)到纖維(wei)內(nei)部,故在(zai)精(jing)煉過程中必(bi)須加入(ru)表(biao)面(mian)(mian)(mian)活性(xing)劑(ji),降(jiang)低溶(rong)液(ye)的(de)表(biao)面(mian)(mian)(mian)張力(li)來加快堿液(ye)的(de)滲透(tou),所以(yi)精(jing)煉所用表(biao)面(mian)(mian)(mian)活性(xing)劑(ji)取決于(yu)它降(jiang)低表(biao)面(mian)(mian)(mian)張力(li)的(de)能(neng)力(li)和滲透(tou)作用速(su)度(du)。
從潤濕(shi)基本方程式(shi)(式(shi)1)來看,由于(yu)滌(di)(di)綸(lun)(lun)為主的(de)(de)新合(he)纖(xian)表(biao)面(mian)(mian)(mian)張(zhang)力(li)為42mN/m左(zuo)右,而精煉(lian)(lian)液的(de)(de)表(biao)面(mian)(mian)(mian)張(zhang)力(li)為35mN/m左(zuo)右,因(yin)此(ci)滌(di)(di)綸(lun)(lun)在精煉(lian)(lian)液中很(hen)容易被精煉(lian)(lian)液所潤濕(shi)。但若液體中含有油蠟(la)(la)(la)(la),使滌(di)(di)綸(lun)(lun)纖(xian)維(wei)和油蠟(la)(la)(la)(la)間的(de)(de)界面(mian)(mian)(mian)張(zhang)力(li)γLS升(sheng)高(gao),并接(jie)近于(yu)滌(di)(di)綸(lun)(lun)纖(xian)維(wei)的(de)(de)表(biao)面(mian)(mian)(mian)張(zhang)力(li),因(yin)此(ci)含油蠟(la)(la)(la)(la)的(de)(de)溶(rong)液不易使滌(di)(di)綸(lun)(lun)纖(xian)維(wei)所潤濕(shi)。若滌(di)(di)綸(lun)(lun)纖(xian)維(wei)上(shang)同時存在油蠟(la)(la)(la)(la)和精煉(lian)(lian)液,即使滌(di)(di)綸(lun)(lun)已(yi)為油蠟(la)(la)(la)(la)所潤濕(shi),因(yin)γ滌(di)(di)蠟(la)(la)(la)(la)>γ滌(di)(di)精煉(lian)(lian)液,滌(di)(di)綸(lun)(lun)上(shang)的(de)(de)油蠟(la)(la)(la)(la)也會自動地(di)收縮成油滴(即θ為90°),然后(hou)便為表(biao)面(mian)(mian)(mian)活性劑所乳化,而從織物上(shang)除去,因(yin)此(ci)只有選擇較低表(biao)面(mian)(mian)(mian)張(zhang)力(li)的(de)(de)物質(γLG)才能使織物潤濕(shi)。
同(tong)時新合纖(xian)上所(suo)含的油脂(zhi),蠟質均(jun)為脂(zhi)肪類物質,從結構的相(xiang)似性(xing)出發,宜采用脂(zhi)肪醇聚氧乙烯醚(mi)與烷基苯酚聚氧乙烯醚(mi)配合使用,且(qie)前(qian)者的潤(run)濕力又超(chao)過后者,有(you)利(li)于降(jiang)低γLG及(ji)γLS,從而提高潤(run)濕效果。
非離子(zi)(zi)表(biao)(biao)面(mian)(mian)(mian)(mian)活(huo)(huo)性(xing)劑(ji)(ji)加入到陰離子(zi)(zi)表(biao)(biao)面(mian)(mian)(mian)(mian)活(huo)(huo)性(xing)劑(ji)(ji)后,非離子(zi)(zi)表(biao)(biao)面(mian)(mian)(mian)(mian)活(huo)(huo)性(xing)劑(ji)(ji)插入到陰離子(zi)(zi)表(biao)(biao)面(mian)(mian)(mian)(mian)活(huo)(huo)性(xing)劑(ji)(ji)膠(jiao)束(shu)中(zhong)形成了混(hun)合膠(jiao)束(shu),其中(zhong)非離子(zi)(zi)表(biao)(biao)面(mian)(mian)(mian)(mian)活(huo)(huo)性(xing)劑(ji)(ji)的(de)聚氧(yang)乙烯(xi)鏈(lian)愈短(duan)或陰離子(zi)(zi)表(biao)(biao)面(mian)(mian)(mian)(mian)活(huo)(huo)性(xing)劑(ji)(ji)疏水基鏈(lian)愈短(duan),則(ze)愈容易插入,從而(er)使(shi)(shi)界面(mian)(mian)(mian)(mian)吸(xi)附速(su)度(du)(du)提(ti)高(gao),表(biao)(biao)面(mian)(mian)(mian)(mian)張力下降,潤(run)(run)濕(shi)(shi)性(xing)提(ti)高(gao)。而(er)且(qie)在(zai)表(biao)(biao)面(mian)(mian)(mian)(mian)活(huo)(huo)性(xing)劑(ji)(ji)濃度(du)(du)低于(yu)(yu)cmc時(shi),由于(yu)(yu)表(biao)(biao)面(mian)(mian)(mian)(mian)活(huo)(huo)性(xing)劑(ji)(ji)在(zai)界面(mian)(mian)(mian)(mian)上(shang)(shang)(shang)單分子(zi)(zi)定(ding)向(xiang)吸(xi)附,隨(sui)著溶液中(zhong)表(biao)(biao)面(mian)(mian)(mian)(mian)活(huo)(huo)性(xing)劑(ji)(ji)濃度(du)(du)增加,界面(mian)(mian)(mian)(mian)上(shang)(shang)(shang)出現飽(bao)和(he)吸(xi)附,而(er)使(shi)(shi)潤(run)(run)濕(shi)(shi)性(xing)提(ti)高(gao)(如表(biao)(biao)3),但當表(biao)(biao)面(mian)(mian)(mian)(mian)活(huo)(huo)性(xing)劑(ji)(ji)濃度(du)(du)高(gao)于(yu)(yu)cmc時(shi),則(ze)在(zai)溶液中(zhong)形成膠(jiao)束(shu),隨(sui)著濃度(du)(du)增加,膠(jiao)束(shu)介離為單分子(zi)(zi)的(de)速(su)度(du)(du)減(jian)慢(man),向(xiang)影響(xiang)了單分子(zi)(zi)在(zai)界面(mian)(mian)(mian)(mian)上(shang)(shang)(shang)的(de)飽(bao)和(he)吸(xi)附,使(shi)(shi)潤(run)(run)濕(shi)(shi)性(xing)下降,所(suo)以作為潤(run)(run)濕(shi)(shi)劑(ji)(ji)使(shi)(shi)用濃度(du)(du)一般不宜(yi)過高(gao),只要略大于(yu)(yu)cmc即可(ke)。