
硅橡膠是指主(zhu)鏈由硅(gui)(gui)和氧原子交替構成(cheng)(cheng),硅(gui)(gui)原子上通(tong)常連(lian)有(you)兩(liang)個有(you)機基(ji)(ji)團的(de)(de)(de)(de)(de)(de)(de)橡(xiang)膠(jiao)。普通(tong)的(de)(de)(de)(de)(de)(de)(de)硅(gui)(gui)橡(xiang)膠(jiao)主(zhu)要由含甲基(ji)(ji)和少量乙烯基(ji)(ji)的(de)(de)(de)(de)(de)(de)(de)硅(gui)(gui)氧鏈節組成(cheng)(cheng)。苯基(ji)(ji)的(de)(de)(de)(de)(de)(de)(de)引(yin)(yin)入(ru)可(ke)提(ti)高(gao)(gao)硅(gui)(gui)橡(xiang)膠(jiao)的(de)(de)(de)(de)(de)(de)(de)耐(nai)高(gao)(gao)、低溫性(xing)(xing)能,三氟丙(bing)基(ji)(ji)及氰基(ji)(ji)的(de)(de)(de)(de)(de)(de)(de)引(yin)(yin)入(ru)則可(ke)提(ti)高(gao)(gao)硅(gui)(gui)橡(xiang)膠(jiao)的(de)(de)(de)(de)(de)(de)(de)耐(nai)溫及耐(nai)油性(xing)(xing)能。硅(gui)(gui)橡(xiang)膠(jiao)耐(nai)低溫性(xing)(xing)能良好,一般(ban)在-55℃下仍能工作(zuo)。引(yin)(yin)入(ru)苯基(ji)(ji)后,可(ke)達-73℃。硅(gui)(gui)橡(xiang)膠(jiao)的(de)(de)(de)(de)(de)(de)(de)耐(nai)熱性(xing)(xing)能也(ye)很突出,在180℃下可(ke)長期工作(zuo),稍高(gao)(gao)于200℃也(ye)能承受(shou)數(shu)周或更長時間仍有(you)彈性(xing)(xing),瞬時可(ke)耐(nai)300℃以上的(de)(de)(de)(de)(de)(de)(de)高(gao)(gao)溫。硅(gui)(gui)橡(xiang)膠(jiao)的(de)(de)(de)(de)(de)(de)(de)透氣(qi)性(xing)(xing)好,氧氣(qi)透過率(lv)在合(he)成(cheng)(cheng)聚(ju)合(he)物中是較高(gao)(gao)的(de)(de)(de)(de)(de)(de)(de)。此(ci)外,硅(gui)(gui)橡(xiang)膠(jiao)還具有(you)生理惰性(xing)(xing)、不會導致(zhi)凝血的(de)(de)(de)(de)(de)(de)(de)突出特(te)性(xing)(xing),因此(ci)在醫用領(ling)域應用廣泛。
主要品種
硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)分(fen)類的(de)方(fang)法(fa)很多,通常(chang)按(an)固化前的(de)形態分(fen)為固體硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)和液體硅(gui)橡(xiang)(xiang)膠(jiao)(jiao);按(an)硫化溫(wen)度分(fen)為室溫(wen)硫化硅(gui)橡(xiang)(xiang)膠(jiao)(jiao),高溫(wen)硫化硅(gui)橡(xiang)(xiang)膠(jiao)(jiao);按(an)所用單(dan)體的(de)不同,可分(fen)為甲基乙(yi)烯基硅(gui)橡(xiang)(xiang)膠(jiao)(jiao),甲基苯基乙(yi)烯基硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)、氟硅(gui),腈硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)等;按(an)性能和用途的(de)不同又可分(fen)為通用型(xing)(xing)(xing)、超耐低溫(wen)型(xing)(xing)(xing)、超耐高溫(wen)型(xing)(xing)(xing)、高強力型(xing)(xing)(xing)、耐油型(xing)(xing)(xing)、醫(yi)用型(xing)(xing)(xing)等等。
發展史
硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)早期(qi)是由美(mei)國(guo)以三氯(lv)(lv)化鐵為催化劑合成(cheng)的(de)(de)(de)。1945年(nian),硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)產(chan)(chan)品問世。1948年(nian),采(cai)用高(gao)比表面積的(de)(de)(de)氣相法白炭(tan)黑(hei)補(bu)強的(de)(de)(de)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)研(yan)(yan)制(zhi)成(cheng)功,使硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)性能(neng)躍升到實用階段,奠定(ding)了現代硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)生(sheng)產(chan)(chan)技術(shu)的(de)(de)(de)基礎。從二甲基二氯(lv)(lv)硅(gui)(gui)烷合成(cheng)開始生(sheng)產(chan)(chan)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)國(guo)家(jia)有美(mei)國(guo)。俄(e)羅斯、德國(guo)、日本(ben)、韓國(guo)和中(zhong)國(guo)等。中(zhong)國(guo)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)工業化研(yan)(yan)究始于1957年(nian),多家(jia)研(yan)(yan)究所和企業陸(lu)續開發出各(ge)種硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)。到2003年(nian)底,中(zhong)國(guo)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)生(sheng)產(chan)(chan)能(neng)力為135千(qian)(qian)噸(dun),其中(zhong)高(gao)溫膠(jiao)(jiao)100千(qian)(qian)噸(dun)。
高溫硫化硅橡膠
高(gao)溫硫(liu)化(hua)(hua)硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)是指(zhi)聚(ju)硅(gui)氧烷變(bian)成(cheng)彈(dan)性(xing)體的過(guo)(guo)程是經過(guo)(guo)高(gao)溫(110-170℃)硫(liu)化(hua)(hua)成(cheng)型(xing)的。它主(zhu)(zhu)要以高(gao)分(fen)子量(liang)的聚(ju)甲(jia)基乙(yi)烯基硅(gui)氧烷為(wei)生膠(jiao)(jiao)(jiao),混入補強(qiang)填料(liao)、硫(liu)化(hua)(hua)劑等,在加(jia)(jia)(jia)熱加(jia)(jia)(jia)壓下硫(liu)化(hua)(hua)成(cheng)彈(dan)性(xing)體。硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)的補強(qiang)主(zhu)(zhu)要是各(ge)種(zhong)(zhong)(zhong)類型(xing)的白炭黑,可使硫(liu)化(hua)(hua)膠(jiao)(jiao)(jiao)的強(qiang)度增加(jia)(jia)(jia)數十(shi)倍。有時為(wei)了降低(di)成(cheng)本或改善膠(jiao)(jiao)(jiao)料(liao)性(xing)能(neng)及賦予硫(liu)化(hua)(hua)膠(jiao)(jiao)(jiao)各(ge)種(zhong)(zhong)(zhong)特殊的性(xing)能(neng),也加(jia)(jia)(jia)入相(xiang)應的各(ge)種(zhong)(zhong)(zhong)添(tian)加(jia)(jia)(jia)劑。硫(liu)化(hua)(hua)劑是各(ge)種(zhong)(zhong)(zhong)有機過(guo)(guo)氧化(hua)(hua)物(wu)或加(jia)(jia)(jia)成(cheng)反應催化(hua)(hua)劑。
加(jia)工成型方(fang)法(fa)如圖所示。一次(ci)硫化(hua)的(de)(de)目(mu)的(de)(de)是(shi)進行高分子鏈(lian)的(de)(de)交(jiao)聯反(fan)應(ying);二次(ci)硫化(hua)的(de)(de)目(mu)的(de)(de)是(shi)進行補充(chong)交(jiao)聯、驅(qu)除硫化(hua)劑分解(jie)產物和其他揮(hui)發性(xing)化(hua)合物以穩定硫化(hua)膠的(de)(de)各項性(xing)能。常用的(de)(de)設備有開放式煉膠機、捏合機及真(zhen)空密煉機。
主要性能
(1)高(gao)(gao)溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)顯著的(de)特(te)征是高(gao)(gao)溫(wen)(wen)(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然(ran)常(chang)溫(wen)(wen)(wen)下(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)強度(du)僅是天(tian)然(ran)橡(xiang)(xiang)(xiang)膠(jiao)或某些(xie)合(he)成橡(xiang)(xiang)(xiang)膠(jiao)的(de)一半,但在200℃以上(shang)的(de)高(gao)(gao)溫(wen)(wen)(wen)環(huan)境下(xia),硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)仍能(neng)(neng)保(bao)持(chi)一定的(de)柔(rou)韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和表(biao)面硬度(du),且力學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)無(wu)(wu)明顯變(bian)化(hua)。(2)低(di)溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)玻璃(li)化(hua)溫(wen)(wen)(wen)度(du)一般(ban)為-70~-50℃,特(te)殊配(pei)方可(ke)達-100℃,表(biao)明其低(di)溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)(you)異(yi)。這對(dui)航(hang)空(kong)(kong)、宇航(hang)工業的(de)意(yi)義重大。(3)耐(nai)候(hou)(hou)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)中Si-O-Si鍵對(dui)氧、臭氧及紫外線等十分穩定,在不加任何添(tian)加劑的(de)情況下(xia),就具(ju)有(you)優(you)(you)良的(de)耐(nai)候(hou)(hou)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)具(ju)有(you)優(you)(you)異(yi)的(de)絕(jue)緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng),耐(nai)電暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)電弧(hu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非常(chang)好。(5)物理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)常(chang)溫(wen)(wen)(wen)下(xia)的(de)物理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)比(bi)通(tong)(tong)用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)差,但在150℃的(de)高(gao)(gao)溫(wen)(wen)(wen)和-50℃的(de)低(di)溫(wen)(wen)(wen)下(xia),其物理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)(you)于通(tong)(tong)用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)。(6)耐(nai)油(you)及化(hua)學試劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)(tong)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)具(ju)有(you)中等的(de)耐(nai)油(you)、耐(nai)溶劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。(7)氣(qi)(qi)體(ti)透過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。室溫(wen)(wen)(wen)下(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)對(dui)空(kong)(kong)氣(qi)(qi)、氮、氧、二(er)氧化(hua)碳(tan)等氣(qi)(qi)體(ti)的(de)透氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比(bi)天(tian)然(ran)橡(xiang)(xiang)(xiang)膠(jiao)高(gao)(gao)出(chu)30-50倍。(8)生理(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)無(wu)(wu)毒,無(wu)(wu)味(wei),無(wu)(wu)嗅(xiu),與人體(ti)組織不粘連,具(ju)有(you)抗(kang)凝(ning)血作用(yong)(yong),對(dui)肌(ji)體(ti)組織的(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常(chang)少(shao)。特(te)別(bie)適合(he)作為醫用(yong)(yong)材料。
硅橡膠的用量
據中國(guo)(guo)汽(qi)(qi)車(che)(che)工業(ye)(ye)協會統計(ji),2012年,汽(qi)(qi)車(che)(che)產(chan)銷(xiao)分別達到1927.18萬輛和(he)1930.64萬輛,同(tong)比分別增(zeng)長4.63%和(he)4.33%,汽(qi)(qi)車(che)(che)工業(ye)(ye)硅(gui)橡(xiang)膠(jiao)的(de)(de)用(yong)量約達2.0萬t。根據觀研天(tian)下(xia)的(de)(de)新研究(jiu),增(zeng)加(jia)(jia)有(you)機(ji)硅(gui)材料在汽(qi)(qi)車(che)(che)零(ling)部件方(fang)面的(de)(de)用(yong)量,可以大(da)幅度(du)提高(gao)(gao)汽(qi)(qi)車(che)(che)的(de)(de)安(an)全性能,因此(ci),汽(qi)(qi)車(che)(che)產(chan)量和(he)單車(che)(che)用(yong)量水平的(de)(de)提高(gao)(gao)都將(jiang)(jiang)推(tui)動汽(qi)(qi)車(che)(che)工業(ye)(ye)對硅(gui)橡(xiang)膠(jiao)需求的(de)(de)增(zeng)加(jia)(jia)。國(guo)(guo)家(jia)鼓勵自主品(pin)牌的(de)(de)汽(qi)(qi)車(che)(che)發(fa)(fa)展,關鍵汽(qi)(qi)車(che)(che)零(ling)部件實現自主化,《2012年度(du)黨政機(ji)關公(gong)務用(yong)車(che)(che)選用(yong)車(che)(che)型目(mu)錄(征求意(yi)見(jian)稿)》為自主品(pin)牌擴(kuo)大(da)在政府采(cai)(cai)購(gou)的(de)(de)市場份額,為改變目(mu)前國(guo)(guo)內(nei)政府采(cai)(cai)購(gou)以合資(zi)品(pin)牌產(chan)品(pin)為主的(de)(de)局(ju)面提供(gong)了(le)保障(zhang)。促進自主品(pin)牌發(fa)(fa)展,國(guo)(guo)產(chan)汽(qi)(qi)車(che)(che)業(ye)(ye)的(de)(de)繁榮將(jiang)(jiang)為汽(qi)(qi)車(che)(che)膠(jiao)的(de)(de)應用(yong)提供(gong)有(you)力保障(zhang)。預測未來3年,我(wo)國(guo)(guo)室溫硫化硅(gui)橡(xiang)膠(jiao)在汽(qi)(qi)車(che)(che)行業(ye)(ye)將(jiang)(jiang)以年均20%增(zeng)長。
此外,硅(gui)(gui)(gui)橡(xiang)膠(jiao)是重(zhong)要的非石(shi)油基合(he)成(cheng)(cheng)(cheng)橡(xiang)膠(jiao),約占(zhan)非石(shi)油基合(he)成(cheng)(cheng)(cheng)橡(xiang)膠(jiao)消費量的98%。但因為(wei)(wei)石(shi)油價(jia)格的大幅上漲,同時(shi)我國在(zai)硅(gui)(gui)(gui)橡(xiang)膠(jiao)的關鍵原料有(you)機硅(gui)(gui)(gui)單(dan)體(ti)(ti)的生(sheng)產(chan)(chan)技(ji)術(shu)方(fang)(fang)面取(qu)得突破,有(you)機硅(gui)(gui)(gui)單(dan)體(ti)(ti)的生(sheng)產(chan)(chan)技(ji)術(shu)在(zai)2005年(nian)前被(bei)幾家(jia)跨(kua)國公司壟斷(duan),但目前我國已(yi)發展成(cheng)(cheng)(cheng)為(wei)(wei)全球有(you)機硅(gui)(gui)(gui)單(dan)體(ti)(ti)第1大國,這2個方(fang)(fang)面原因使(shi)硅(gui)(gui)(gui)橡(xiang)膠(jiao)的價(jia)格從2011年(nian)起開始低于石(shi)油基合(he)成(cheng)(cheng)(cheng)橡(xiang)膠(jiao),僅約為(wei)(wei)大宗石(shi)油基橡(xiang)膠(jiao)的80%~90%,成(cheng)(cheng)(cheng)為(wei)(wei)廉價(jia)的合(he)成(cheng)(cheng)(cheng)橡(xiang)膠(jiao),并開始大規模替(ti)代石(shi)油基合(he)成(cheng)(cheng)(cheng)橡(xiang)膠(jiao)。這將極(ji)大拓展有(you)機硅(gui)(gui)(gui)產(chan)(chan)業的市(shi)場(chang)空間,同時(shi)將帶動硅(gui)(gui)(gui)油、硅(gui)(gui)(gui)烷偶聯劑(ji)和硅(gui)(gui)(gui)樹脂(zhi)等其他有(you)機硅(gui)(gui)(gui)產(chan)(chan)品的消費。