
硅橡膠是指主鏈(lian)由硅(gui)(gui)(gui)和(he)氧(yang)原(yuan)子交替構成(cheng),硅(gui)(gui)(gui)原(yuan)子上通(tong)常連有(you)(you)兩個有(you)(you)機基(ji)團(tuan)的(de)(de)(de)橡膠(jiao)。普(pu)通(tong)的(de)(de)(de)硅(gui)(gui)(gui)橡膠(jiao)主要由含甲(jia)基(ji)和(he)少量乙烯基(ji)的(de)(de)(de)硅(gui)(gui)(gui)氧(yang)鏈(lian)節組成(cheng)。苯基(ji)的(de)(de)(de)引入可(ke)(ke)提(ti)高(gao)硅(gui)(gui)(gui)橡膠(jiao)的(de)(de)(de)耐(nai)(nai)(nai)高(gao)、低溫(wen)(wen)性(xing)(xing)能(neng)(neng),三(san)氟丙基(ji)及氰基(ji)的(de)(de)(de)引入則可(ke)(ke)提(ti)高(gao)硅(gui)(gui)(gui)橡膠(jiao)的(de)(de)(de)耐(nai)(nai)(nai)溫(wen)(wen)及耐(nai)(nai)(nai)油性(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)橡膠(jiao)耐(nai)(nai)(nai)低溫(wen)(wen)性(xing)(xing)能(neng)(neng)良好(hao),一般在-55℃下(xia)仍(reng)能(neng)(neng)工作(zuo)。引入苯基(ji)后,可(ke)(ke)達-73℃。硅(gui)(gui)(gui)橡膠(jiao)的(de)(de)(de)耐(nai)(nai)(nai)熱性(xing)(xing)能(neng)(neng)也很突出,在180℃下(xia)可(ke)(ke)長期工作(zuo),稍高(gao)于200℃也能(neng)(neng)承受數周(zhou)或更(geng)長時間仍(reng)有(you)(you)彈性(xing)(xing),瞬時可(ke)(ke)耐(nai)(nai)(nai)300℃以上的(de)(de)(de)高(gao)溫(wen)(wen)。硅(gui)(gui)(gui)橡膠(jiao)的(de)(de)(de)透(tou)氣性(xing)(xing)好(hao),氧(yang)氣透(tou)過率在合成(cheng)聚(ju)合物中是較(jiao)高(gao)的(de)(de)(de)。此外,硅(gui)(gui)(gui)橡膠(jiao)還具有(you)(you)生(sheng)理惰性(xing)(xing)、不會導致凝(ning)血(xue)的(de)(de)(de)突出特(te)性(xing)(xing),因此在醫用領域應(ying)用廣泛。
主要品種
硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)分類的方法(fa)很多,通(tong)常按(an)固(gu)化(hua)(hua)(hua)前的形態分為(wei)固(gu)體(ti)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)和液體(ti)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao);按(an)硫化(hua)(hua)(hua)溫(wen)(wen)度分為(wei)室溫(wen)(wen)硫化(hua)(hua)(hua)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao),高溫(wen)(wen)硫化(hua)(hua)(hua)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao);按(an)所用(yong)(yong)單體(ti)的不(bu)同(tong),可分為(wei)甲(jia)(jia)基(ji)(ji)乙烯基(ji)(ji)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao),甲(jia)(jia)基(ji)(ji)苯基(ji)(ji)乙烯基(ji)(ji)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)、氟硅(gui)(gui),腈硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)等(deng);按(an)性(xing)能和用(yong)(yong)途的不(bu)同(tong)又可分為(wei)通(tong)用(yong)(yong)型(xing)(xing)(xing)、超耐(nai)低(di)溫(wen)(wen)型(xing)(xing)(xing)、超耐(nai)高溫(wen)(wen)型(xing)(xing)(xing)、高強力型(xing)(xing)(xing)、耐(nai)油型(xing)(xing)(xing)、醫用(yong)(yong)型(xing)(xing)(xing)等(deng)等(deng)。
發展史
硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)早期是(shi)由美國(guo)(guo)(guo)(guo)以三氯(lv)化鐵為(wei)催化劑合成的(de)(de)。1945年,硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)產(chan)(chan)(chan)品問世。1948年,采(cai)用(yong)高比表面積的(de)(de)氣相(xiang)法白炭黑補強的(de)(de)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)研制成功(gong),使(shi)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)性(xing)能(neng)躍升到(dao)實用(yong)階段(duan),奠定了(le)現代(dai)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)生(sheng)產(chan)(chan)(chan)技術(shu)的(de)(de)基礎。從二(er)甲(jia)基二(er)氯(lv)硅(gui)烷合成開始(shi)生(sheng)產(chan)(chan)(chan)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)國(guo)(guo)(guo)(guo)家有美國(guo)(guo)(guo)(guo)。俄羅(luo)斯、德(de)國(guo)(guo)(guo)(guo)、日本、韓國(guo)(guo)(guo)(guo)和中(zhong)國(guo)(guo)(guo)(guo)等。中(zhong)國(guo)(guo)(guo)(guo)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)工業化研究始(shi)于1957年,多家研究所和企業陸(lu)續開發(fa)出各種硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)。到(dao)2003年底,中(zhong)國(guo)(guo)(guo)(guo)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)生(sheng)產(chan)(chan)(chan)能(neng)力為(wei)135千噸,其中(zhong)高溫膠(jiao)(jiao)100千噸。
高溫硫化硅橡膠
高溫硫(liu)(liu)化硅橡膠是(shi)指聚(ju)硅氧(yang)烷變成(cheng)(cheng)彈性體的(de)(de)過(guo)(guo)程是(shi)經過(guo)(guo)高溫(110-170℃)硫(liu)(liu)化成(cheng)(cheng)型(xing)的(de)(de)。它主要以高分(fen)子量的(de)(de)聚(ju)甲基乙(yi)烯基硅氧(yang)烷為生(sheng)膠,混入補強(qiang)填(tian)料(liao)、硫(liu)(liu)化劑等,在(zai)加(jia)(jia)熱加(jia)(jia)壓下(xia)硫(liu)(liu)化成(cheng)(cheng)彈性體。硅橡膠的(de)(de)補強(qiang)主要是(shi)各(ge)種(zhong)類型(xing)的(de)(de)白炭黑,可使硫(liu)(liu)化膠的(de)(de)強(qiang)度(du)增加(jia)(jia)數十倍。有時為了(le)降低成(cheng)(cheng)本或改(gai)善(shan)膠料(liao)性能及賦予(yu)硫(liu)(liu)化膠各(ge)種(zhong)特殊的(de)(de)性能,也(ye)加(jia)(jia)入相應(ying)的(de)(de)各(ge)種(zhong)添加(jia)(jia)劑。硫(liu)(liu)化劑是(shi)各(ge)種(zhong)有機過(guo)(guo)氧(yang)化物或加(jia)(jia)成(cheng)(cheng)反應(ying)催化劑。
加(jia)工成型(xing)方(fang)法如圖所示。一次硫(liu)化(hua)的(de)目(mu)的(de)是進(jin)行高分子鏈的(de)交(jiao)聯(lian)反應;二次硫(liu)化(hua)的(de)目(mu)的(de)是進(jin)行補(bu)充交(jiao)聯(lian)、驅除硫(liu)化(hua)劑分解產物和其他揮發性化(hua)合(he)物以穩定硫(liu)化(hua)膠的(de)各項性能(neng)。常(chang)用的(de)設備有(you)開放式煉(lian)膠機(ji)、捏合(he)機(ji)及真空密煉(lian)機(ji)。
主要性能
(1)高(gao)溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)顯著的(de)(de)(de)特(te)征是高(gao)溫(wen)(wen)(wen)(wen)穩定性(xing)(xing)(xing)(xing)(xing),雖然(ran)常(chang)溫(wen)(wen)(wen)(wen)下(xia)(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)強度僅是天(tian)然(ran)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)或某(mou)些合成(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)一(yi)(yi)半,但在200℃以上的(de)(de)(de)高(gao)溫(wen)(wen)(wen)(wen)環境下(xia)(xia)(xia),硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)仍能(neng)(neng)(neng)(neng)(neng)保持一(yi)(yi)定的(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)和(he)表面硬度,且力學性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)無明顯變化。(2)低(di)溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)玻璃化溫(wen)(wen)(wen)(wen)度一(yi)(yi)般為-70~-50℃,特(te)殊配方可達-100℃,表明其低(di)溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)優(you)(you)異。這對(dui)航空、宇(yu)航工(gong)業的(de)(de)(de)意義重(zhong)大。(3)耐候(hou)性(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)中Si-O-Si鍵對(dui)氧、臭氧及紫外線(xian)等十(shi)分穩定,在不加(jia)任(ren)何添加(jia)劑的(de)(de)(de)情況下(xia)(xia)(xia),就具(ju)有優(you)(you)良的(de)(de)(de)耐候(hou)性(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)具(ju)有優(you)(you)異的(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng),耐電(dian)暈性(xing)(xing)(xing)(xing)(xing)和(he)耐電(dian)弧性(xing)(xing)(xing)(xing)(xing)也非(fei)常(chang)好。(5)物(wu)理(li)機械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)常(chang)溫(wen)(wen)(wen)(wen)下(xia)(xia)(xia)的(de)(de)(de)物(wu)理(li)機械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)比通(tong)用橡(xiang)(xiang)(xiang)膠(jiao)(jiao)差(cha),但在150℃的(de)(de)(de)高(gao)溫(wen)(wen)(wen)(wen)和(he)-50℃的(de)(de)(de)低(di)溫(wen)(wen)(wen)(wen)下(xia)(xia)(xia),其物(wu)理(li)機械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)優(you)(you)于通(tong)用橡(xiang)(xiang)(xiang)膠(jiao)(jiao)。(6)耐油及化學試劑性(xing)(xing)(xing)(xing)(xing)。普通(tong)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)具(ju)有中等的(de)(de)(de)耐油、耐溶劑性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。(7)氣(qi)(qi)體(ti)(ti)透(tou)過(guo)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。室溫(wen)(wen)(wen)(wen)下(xia)(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)對(dui)空氣(qi)(qi)、氮、氧、二氧化碳等氣(qi)(qi)體(ti)(ti)的(de)(de)(de)透(tou)氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)比天(tian)然(ran)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)高(gao)出30-50倍。(8)生理(li)惰性(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)無毒(du),無味(wei),無嗅,與人體(ti)(ti)組(zu)織不粘連,具(ju)有抗凝(ning)血作用,對(dui)肌(ji)體(ti)(ti)組(zu)織的(de)(de)(de)反應(ying)性(xing)(xing)(xing)(xing)(xing)非(fei)常(chang)少。特(te)別適合作為醫用材料(liao)。
硅橡膠的用量
據(ju)中國(guo)(guo)汽(qi)(qi)(qi)(qi)(qi)車工業(ye)(ye)協(xie)會統(tong)計(ji),2012年,汽(qi)(qi)(qi)(qi)(qi)車產銷分別(bie)達(da)到1927.18萬輛(liang)和1930.64萬輛(liang),同比(bi)分別(bie)增長(chang)4.63%和4.33%,汽(qi)(qi)(qi)(qi)(qi)車工業(ye)(ye)硅(gui)橡(xiang)膠(jiao)的(de)(de)用(yong)(yong)(yong)量約達(da)2.0萬t。根據(ju)觀(guan)研(yan)天下的(de)(de)新研(yan)究,增加(jia)有機(ji)硅(gui)材料在(zai)(zai)汽(qi)(qi)(qi)(qi)(qi)車零部件(jian)方面的(de)(de)用(yong)(yong)(yong)量,可以(yi)大幅度(du)提高汽(qi)(qi)(qi)(qi)(qi)車的(de)(de)安全性能,因此(ci),汽(qi)(qi)(qi)(qi)(qi)車產量和單車用(yong)(yong)(yong)量水平的(de)(de)提高都將(jiang)推(tui)動(dong)汽(qi)(qi)(qi)(qi)(qi)車工業(ye)(ye)對硅(gui)橡(xiang)膠(jiao)需求(qiu)的(de)(de)增加(jia)。國(guo)(guo)家鼓勵(li)自主(zhu)(zhu)(zhu)品牌的(de)(de)汽(qi)(qi)(qi)(qi)(qi)車發展,關(guan)鍵汽(qi)(qi)(qi)(qi)(qi)車零部件(jian)實現自主(zhu)(zhu)(zhu)化,《2012年度(du)黨政(zheng)(zheng)機(ji)關(guan)公務用(yong)(yong)(yong)車選用(yong)(yong)(yong)車型目錄(lu)(征求(qiu)意(yi)見稿)》為(wei)(wei)自主(zhu)(zhu)(zhu)品牌擴大在(zai)(zai)政(zheng)(zheng)府(fu)(fu)采購的(de)(de)市(shi)場(chang)份額,為(wei)(wei)改變(bian)目前國(guo)(guo)內政(zheng)(zheng)府(fu)(fu)采購以(yi)合資(zi)品牌產品為(wei)(wei)主(zhu)(zhu)(zhu)的(de)(de)局(ju)面提供了保障(zhang)。促(cu)進(jin)自主(zhu)(zhu)(zhu)品牌發展,國(guo)(guo)產汽(qi)(qi)(qi)(qi)(qi)車業(ye)(ye)的(de)(de)繁榮將(jiang)為(wei)(wei)汽(qi)(qi)(qi)(qi)(qi)車膠(jiao)的(de)(de)應用(yong)(yong)(yong)提供有力保障(zhang)。預測未來3年,我國(guo)(guo)室溫(wen)硫化硅(gui)橡(xiang)膠(jiao)在(zai)(zai)汽(qi)(qi)(qi)(qi)(qi)車行業(ye)(ye)將(jiang)以(yi)年均20%增長(chang)。
此外,硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)是重要(yao)的(de)非石油(you)基(ji)合(he)成橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao),約(yue)占非石油(you)基(ji)合(he)成橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)消費(fei)量的(de)98%。但因為(wei)(wei)石油(you)價(jia)格的(de)大(da)(da)(da)(da)幅上漲,同時我國在(zai)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)關鍵原(yuan)料有機硅(gui)(gui)(gui)單體的(de)生產技術(shu)方(fang)面(mian)取(qu)得突破,有機硅(gui)(gui)(gui)單體的(de)生產技術(shu)在(zai)2005年前被幾家跨國公司壟斷,但目前我國已(yi)發展成為(wei)(wei)全球有機硅(gui)(gui)(gui)單體第1大(da)(da)(da)(da)國,這2個方(fang)面(mian)原(yuan)因使硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)價(jia)格從(cong)2011年起開(kai)始低于石油(you)基(ji)合(he)成橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao),僅約(yue)為(wei)(wei)大(da)(da)(da)(da)宗石油(you)基(ji)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)80%~90%,成為(wei)(wei)廉(lian)價(jia)的(de)合(he)成橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao),并開(kai)始大(da)(da)(da)(da)規模(mo)替代石油(you)基(ji)合(he)成橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)。這將極大(da)(da)(da)(da)拓(tuo)展有機硅(gui)(gui)(gui)產業的(de)市場(chang)空間,同時將帶動硅(gui)(gui)(gui)油(you)、硅(gui)(gui)(gui)烷(wan)偶聯劑和硅(gui)(gui)(gui)樹脂(zhi)等其他有機硅(gui)(gui)(gui)產品的(de)消費(fei)。