
硅橡膠是指(zhi)主鏈由硅(gui)(gui)(gui)(gui)和氧(yang)(yang)(yang)原(yuan)子(zi)交替構成,硅(gui)(gui)(gui)(gui)原(yuan)子(zi)上通常(chang)連有(you)(you)兩個(ge)有(you)(you)機基(ji)團的(de)(de)(de)(de)橡(xiang)(xiang)膠(jiao)。普(pu)通的(de)(de)(de)(de)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)主要(yao)由含甲基(ji)和少量乙(yi)烯(xi)基(ji)的(de)(de)(de)(de)硅(gui)(gui)(gui)(gui)氧(yang)(yang)(yang)鏈節(jie)組成。苯基(ji)的(de)(de)(de)(de)引(yin)入可(ke)提高(gao)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)耐高(gao)、低溫(wen)(wen)性能(neng)(neng),三氟丙(bing)基(ji)及(ji)氰基(ji)的(de)(de)(de)(de)引(yin)入則可(ke)提高(gao)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)耐溫(wen)(wen)及(ji)耐油性能(neng)(neng)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)耐低溫(wen)(wen)性能(neng)(neng)良好,一般在(zai)(zai)-55℃下仍(reng)能(neng)(neng)工作。引(yin)入苯基(ji)后(hou),可(ke)達(da)-73℃。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)耐熱性能(neng)(neng)也(ye)很突出,在(zai)(zai)180℃下可(ke)長期工作,稍高(gao)于(yu)200℃也(ye)能(neng)(neng)承受數周或更長時間仍(reng)有(you)(you)彈(dan)性,瞬時可(ke)耐300℃以上的(de)(de)(de)(de)高(gao)溫(wen)(wen)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)透氣性好,氧(yang)(yang)(yang)氣透過(guo)率在(zai)(zai)合成聚合物中是較高(gao)的(de)(de)(de)(de)。此外(wai),硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)還具有(you)(you)生理惰性、不會(hui)導致凝血的(de)(de)(de)(de)突出特性,因此在(zai)(zai)醫用領域(yu)應用廣泛。
主要品種
硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)分類的方法很多,通常按(an)固(gu)化(hua)前(qian)的形態分為固(gu)體硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)和液體硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao);按(an)硫化(hua)溫(wen)(wen)度分為室溫(wen)(wen)硫化(hua)硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao),高溫(wen)(wen)硫化(hua)硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao);按(an)所用單(dan)體的不(bu)同,可(ke)(ke)分為甲基(ji)乙烯(xi)基(ji)硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao),甲基(ji)苯基(ji)乙烯(xi)基(ji)硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)、氟硅,腈硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)等(deng);按(an)性能和用途的不(bu)同又可(ke)(ke)分為通用型(xing)、超(chao)耐(nai)低溫(wen)(wen)型(xing)、超(chao)耐(nai)高溫(wen)(wen)型(xing)、高強力(li)型(xing)、耐(nai)油型(xing)、醫(yi)用型(xing)等(deng)等(deng)。
發展史
硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)早期是由(you)美(mei)國(guo)(guo)(guo)以三氯(lv)化鐵為催(cui)化劑合(he)成的。1945年(nian),硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)產(chan)品問世(shi)。1948年(nian),采用(yong)高比表面積的氣相(xiang)法白(bai)炭黑補強的硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)研(yan)制成功,使(shi)硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的性(xing)能躍升(sheng)到(dao)實(shi)用(yong)階段,奠定了(le)現(xian)代(dai)硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)生(sheng)(sheng)產(chan)技(ji)術的基(ji)礎。從二(er)甲基(ji)二(er)氯(lv)硅(gui)(gui)(gui)(gui)烷合(he)成開始生(sheng)(sheng)產(chan)硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的國(guo)(guo)(guo)家有美(mei)國(guo)(guo)(guo)。俄羅斯(si)、德國(guo)(guo)(guo)、日本、韓國(guo)(guo)(guo)和中國(guo)(guo)(guo)等(deng)。中國(guo)(guo)(guo)硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的工業(ye)化研(yan)究(jiu)(jiu)始于1957年(nian),多家研(yan)究(jiu)(jiu)所和企業(ye)陸續開發出各種硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)。到(dao)2003年(nian)底,中國(guo)(guo)(guo)硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)生(sheng)(sheng)產(chan)能力(li)為135千噸,其中高溫膠(jiao)(jiao)100千噸。
高溫硫化硅橡膠
高(gao)溫硫(liu)(liu)(liu)化(hua)硅橡膠(jiao)(jiao)是指(zhi)聚(ju)硅氧烷變(bian)成彈性(xing)體的(de)過(guo)程(cheng)是經過(guo)高(gao)溫(110-170℃)硫(liu)(liu)(liu)化(hua)成型的(de)。它主要以高(gao)分子量的(de)聚(ju)甲基(ji)乙(yi)烯(xi)基(ji)硅氧烷為生膠(jiao)(jiao),混入補強填料、硫(liu)(liu)(liu)化(hua)劑(ji)等,在(zai)加(jia)熱加(jia)壓(ya)下硫(liu)(liu)(liu)化(hua)成彈性(xing)體。硅橡膠(jiao)(jiao)的(de)補強主要是各(ge)種(zhong)類型的(de)白炭黑,可(ke)使硫(liu)(liu)(liu)化(hua)膠(jiao)(jiao)的(de)強度增加(jia)數(shu)十倍。有時為了降低成本或改善膠(jiao)(jiao)料性(xing)能(neng)及賦(fu)予硫(liu)(liu)(liu)化(hua)膠(jiao)(jiao)各(ge)種(zhong)特(te)殊的(de)性(xing)能(neng),也加(jia)入相(xiang)應的(de)各(ge)種(zhong)添加(jia)劑(ji)。硫(liu)(liu)(liu)化(hua)劑(ji)是各(ge)種(zhong)有機過(guo)氧化(hua)物或加(jia)成反應催化(hua)劑(ji)。
加工成(cheng)型方法如圖(tu)所示(shi)。一次(ci)硫化(hua)(hua)的(de)目(mu)的(de)是進行高分子鏈(lian)的(de)交聯(lian)反應(ying);二次(ci)硫化(hua)(hua)的(de)目(mu)的(de)是進行補充交聯(lian)、驅除硫化(hua)(hua)劑分解(jie)產物和其他揮(hui)發性化(hua)(hua)合(he)物以穩定硫化(hua)(hua)膠(jiao)的(de)各(ge)項性能。常用(yong)的(de)設備有(you)開放式煉膠(jiao)機(ji)(ji)、捏合(he)機(ji)(ji)及真空(kong)密煉機(ji)(ji)。
主要性能
(1)高(gao)(gao)溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)。硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)顯(xian)(xian)著的(de)(de)(de)特征是高(gao)(gao)溫(wen)(wen)(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing),雖然常(chang)溫(wen)(wen)(wen)下(xia)硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)強度(du)僅(jin)是天然橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)或某些合(he)成橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)一半,但(dan)在200℃以上的(de)(de)(de)高(gao)(gao)溫(wen)(wen)(wen)環境(jing)下(xia),硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)仍(reng)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)保持一定的(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)、回彈(dan)性(xing)(xing)(xing)(xing)(xing)(xing)和表面(mian)硬(ying)度(du),且力學(xue)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)無(wu)明顯(xian)(xian)變化(hua)。(2)低溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)玻(bo)璃化(hua)溫(wen)(wen)(wen)度(du)一般為(wei)-70~-50℃,特殊配方(fang)可達-100℃,表明其低溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)優(you)異。這對(dui)航(hang)空(kong)、宇航(hang)工業(ye)的(de)(de)(de)意義重大。(3)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵對(dui)氧、臭氧及紫外線等(deng)十分(fen)穩定,在不(bu)加(jia)任何添(tian)加(jia)劑(ji)的(de)(de)(de)情況下(xia),就(jiu)具(ju)(ju)有優(you)良的(de)(de)(de)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)。硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)(ju)有優(you)異的(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng),耐(nai)電(dian)暈性(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)電(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)也非常(chang)好。(5)物(wu)理(li)(li)機(ji)械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)。硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)常(chang)溫(wen)(wen)(wen)下(xia)的(de)(de)(de)物(wu)理(li)(li)機(ji)械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)比通(tong)用(yong)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)差,但(dan)在150℃的(de)(de)(de)高(gao)(gao)溫(wen)(wen)(wen)和-50℃的(de)(de)(de)低溫(wen)(wen)(wen)下(xia),其物(wu)理(li)(li)機(ji)械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)優(you)于(yu)通(tong)用(yong)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)油及化(hua)學(xue)試劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)(ju)有中等(deng)的(de)(de)(de)耐(nai)油、耐(nai)溶劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)。(7)氣(qi)體(ti)(ti)透(tou)過性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)(neng)。室溫(wen)(wen)(wen)下(xia)硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)對(dui)空(kong)氣(qi)、氮、氧、二氧化(hua)碳等(deng)氣(qi)體(ti)(ti)的(de)(de)(de)透(tou)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)比天然橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)高(gao)(gao)出30-50倍。(8)生理(li)(li)惰(duo)性(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)無(wu)毒,無(wu)味,無(wu)嗅(xiu),與人體(ti)(ti)組織不(bu)粘連,具(ju)(ju)有抗凝血作(zuo)用(yong),對(dui)肌體(ti)(ti)組織的(de)(de)(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)非常(chang)少。特別(bie)適合(he)作(zuo)為(wei)醫用(yong)材料。
硅橡膠的用量
據(ju)中國汽(qi)(qi)車(che)(che)工(gong)(gong)業(ye)協(xie)會(hui)統(tong)計,2012年(nian),汽(qi)(qi)車(che)(che)產(chan)銷分別達到1927.18萬(wan)輛和1930.64萬(wan)輛,同比(bi)分別增(zeng)長(chang)4.63%和4.33%,汽(qi)(qi)車(che)(che)工(gong)(gong)業(ye)硅橡(xiang)膠的(de)用量(liang)約達2.0萬(wan)t。根據(ju)觀研(yan)天下的(de)新研(yan)究,增(zeng)加有(you)機(ji)硅材料在(zai)(zai)汽(qi)(qi)車(che)(che)零部(bu)件方(fang)面的(de)用量(liang),可以大幅度(du)(du)提(ti)高汽(qi)(qi)車(che)(che)的(de)安全性(xing)能(neng),因(yin)此,汽(qi)(qi)車(che)(che)產(chan)量(liang)和單(dan)車(che)(che)用量(liang)水平的(de)提(ti)高都(dou)將(jiang)推動汽(qi)(qi)車(che)(che)工(gong)(gong)業(ye)對硅橡(xiang)膠需(xu)求的(de)增(zeng)加。國家鼓(gu)勵自主(zhu)品牌(pai)的(de)汽(qi)(qi)車(che)(che)發展(zhan),關(guan)鍵汽(qi)(qi)車(che)(che)零部(bu)件實現(xian)自主(zhu)化,《2012年(nian)度(du)(du)黨政機(ji)關(guan)公(gong)務用車(che)(che)選用車(che)(che)型目錄(征求意見(jian)稿(gao))》為自主(zhu)品牌(pai)擴大在(zai)(zai)政府(fu)采購(gou)(gou)的(de)市場份額,為改變(bian)目前(qian)國內政府(fu)采購(gou)(gou)以合(he)資品牌(pai)產(chan)品為主(zhu)的(de)局面提(ti)供了保障(zhang)。促進(jin)自主(zhu)品牌(pai)發展(zhan),國產(chan)汽(qi)(qi)車(che)(che)業(ye)的(de)繁榮將(jiang)為汽(qi)(qi)車(che)(che)膠的(de)應用提(ti)供有(you)力(li)保障(zhang)。預測未來3年(nian),我(wo)國室(shi)溫硫化硅橡(xiang)膠在(zai)(zai)汽(qi)(qi)車(che)(che)行(xing)業(ye)將(jiang)以年(nian)均20%增(zeng)長(chang)。
此外,硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)是重要的(de)(de)非石油(you)(you)基合(he)(he)成(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao),約占非石油(you)(you)基合(he)(he)成(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)消費量的(de)(de)98%。但(dan)因為(wei)石油(you)(you)價(jia)(jia)格的(de)(de)大(da)幅(fu)上漲(zhang),同時我國在(zai)(zai)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)關鍵原料有機(ji)硅(gui)(gui)單體(ti)的(de)(de)生(sheng)(sheng)產(chan)(chan)技術方(fang)面取得(de)突破(po),有機(ji)硅(gui)(gui)單體(ti)的(de)(de)生(sheng)(sheng)產(chan)(chan)技術在(zai)(zai)2005年前(qian)被幾家跨(kua)國公司壟斷,但(dan)目前(qian)我國已發展成(cheng)為(wei)全球(qiu)有機(ji)硅(gui)(gui)單體(ti)第1大(da)國,這2個方(fang)面原因使硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)價(jia)(jia)格從2011年起(qi)開(kai)始(shi)低于石油(you)(you)基合(he)(he)成(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao),僅(jin)約為(wei)大(da)宗(zong)石油(you)(you)基橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)80%~90%,成(cheng)為(wei)廉價(jia)(jia)的(de)(de)合(he)(he)成(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao),并(bing)開(kai)始(shi)大(da)規模替代(dai)石油(you)(you)基合(he)(he)成(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)。這將極大(da)拓(tuo)展有機(ji)硅(gui)(gui)產(chan)(chan)業的(de)(de)市場空間(jian),同時將帶(dai)動(dong)硅(gui)(gui)油(you)(you)、硅(gui)(gui)烷(wan)偶聯(lian)劑(ji)和硅(gui)(gui)樹脂等其他有機(ji)硅(gui)(gui)產(chan)(chan)品的(de)(de)消費。