硅橡膠是(shi)指主鏈由(you)硅(gui)和氧(yang)原子交替(ti)構成,硅(gui)原子上通(tong)常連有兩(liang)個有機基(ji)(ji)團的(de)(de)橡(xiang)(xiang)(xiang)膠(jiao)。普通(tong)的(de)(de)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)主要由(you)含甲基(ji)(ji)和少量乙(yi)烯基(ji)(ji)的(de)(de)硅(gui)氧(yang)鏈節(jie)組成。苯基(ji)(ji)的(de)(de)引入(ru)(ru)可(ke)提高硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)耐高、低(di)溫性(xing)能(neng),三氟丙基(ji)(ji)及氰(qing)基(ji)(ji)的(de)(de)引入(ru)(ru)則可(ke)提高硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)耐溫及耐油性(xing)能(neng)。硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)耐低(di)溫性(xing)能(neng)良好,一般在(zai)-55℃下仍(reng)能(neng)工(gong)作。引入(ru)(ru)苯基(ji)(ji)后,可(ke)達-73℃。硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)耐熱(re)性(xing)能(neng)也很突出,在(zai)180℃下可(ke)長期工(gong)作,稍(shao)高于200℃也能(neng)承(cheng)受數(shu)周或更長時(shi)間仍(reng)有彈性(xing),瞬(shun)時(shi)可(ke)耐300℃以上的(de)(de)高溫。硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)透氣性(xing)好,氧(yang)氣透過率在(zai)合(he)成聚合(he)物中是(shi)較高的(de)(de)。此外,硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)還具(ju)有生(sheng)理惰性(xing)、不(bu)會(hui)導致凝血的(de)(de)突出特性(xing),因此在(zai)醫用領域應(ying)用廣(guang)泛。
主要品種
硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠分(fen)類的(de)(de)(de)方法很多,通常按固化(hua)前的(de)(de)(de)形態(tai)分(fen)為(wei)(wei)固體硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠和液體硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠;按硫化(hua)溫(wen)度(du)分(fen)為(wei)(wei)室(shi)溫(wen)硫化(hua)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠,高(gao)(gao)溫(wen)硫化(hua)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠;按所用單體的(de)(de)(de)不同,可分(fen)為(wei)(wei)甲基乙烯基硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠,甲基苯(ben)基乙烯基硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠、氟(fu)硅(gui)(gui)(gui),腈硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠等(deng);按性能和用途的(de)(de)(de)不同又可分(fen)為(wei)(wei)通用型(xing)(xing)(xing)、超(chao)耐(nai)低(di)溫(wen)型(xing)(xing)(xing)、超(chao)耐(nai)高(gao)(gao)溫(wen)型(xing)(xing)(xing)、高(gao)(gao)強(qiang)力型(xing)(xing)(xing)、耐(nai)油型(xing)(xing)(xing)、醫用型(xing)(xing)(xing)等(deng)等(deng)。
發展史
硅(gui)(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)早期是由美國(guo)(guo)以三氯化鐵為催化劑(ji)合(he)(he)成的(de)(de)。1945年(nian),硅(gui)(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)產品問世。1948年(nian),采(cai)用(yong)高比表面(mian)積的(de)(de)氣相法白炭黑(hei)補強的(de)(de)硅(gui)(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)研(yan)制(zhi)成功,使硅(gui)(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)性能躍升到實(shi)用(yong)階段,奠(dian)定了現代硅(gui)(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)生(sheng)產技術的(de)(de)基礎。從(cong)二(er)甲基二(er)氯硅(gui)(gui)(gui)(gui)(gui)(gui)(gui)烷合(he)(he)成開始生(sheng)產硅(gui)(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)國(guo)(guo)家有美國(guo)(guo)。俄羅斯、德國(guo)(guo)、日本、韓(han)國(guo)(guo)和中(zhong)國(guo)(guo)等。中(zhong)國(guo)(guo)硅(gui)(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)工(gong)業化研(yan)究(jiu)始于(yu)1957年(nian),多家研(yan)究(jiu)所和企業陸(lu)續開發出各種(zhong)硅(gui)(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)。到2003年(nian)底,中(zhong)國(guo)(guo)硅(gui)(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)生(sheng)產能力為135千(qian)噸,其中(zhong)高溫膠(jiao)(jiao)(jiao)100千(qian)噸。
高溫硫化硅橡膠
高溫(wen)硫(liu)化(hua)硅(gui)橡膠(jiao)(jiao)(jiao)是指(zhi)聚(ju)硅(gui)氧烷變(bian)成彈性(xing)體(ti)的(de)(de)過(guo)程是經過(guo)高溫(wen)(110-170℃)硫(liu)化(hua)成型的(de)(de)。它主要(yao)以高分子量(liang)的(de)(de)聚(ju)甲基乙(yi)烯(xi)基硅(gui)氧烷為(wei)生膠(jiao)(jiao)(jiao),混入(ru)補(bu)強(qiang)填料、硫(liu)化(hua)劑(ji)等,在加熱(re)加壓(ya)下硫(liu)化(hua)成彈性(xing)體(ti)。硅(gui)橡膠(jiao)(jiao)(jiao)的(de)(de)補(bu)強(qiang)主要(yao)是各種(zhong)類(lei)型的(de)(de)白(bai)炭黑,可(ke)使(shi)硫(liu)化(hua)膠(jiao)(jiao)(jiao)的(de)(de)強(qiang)度增加數十倍。有時(shi)為(wei)了降低成本(ben)或改善膠(jiao)(jiao)(jiao)料性(xing)能(neng)(neng)及賦予硫(liu)化(hua)膠(jiao)(jiao)(jiao)各種(zhong)特殊的(de)(de)性(xing)能(neng)(neng),也加入(ru)相應的(de)(de)各種(zhong)添加劑(ji)。硫(liu)化(hua)劑(ji)是各種(zhong)有機過(guo)氧化(hua)物(wu)或加成反應催化(hua)劑(ji)。
加(jia)工成型(xing)方法(fa)如圖(tu)所示。一次(ci)(ci)硫(liu)(liu)化(hua)的(de)(de)目(mu)的(de)(de)是進(jin)(jin)行(xing)高(gao)分(fen)子鏈的(de)(de)交聯反應;二(er)次(ci)(ci)硫(liu)(liu)化(hua)的(de)(de)目(mu)的(de)(de)是進(jin)(jin)行(xing)補充交聯、驅除(chu)硫(liu)(liu)化(hua)劑(ji)分(fen)解產物和其(qi)他(ta)揮發(fa)性化(hua)合物以穩定硫(liu)(liu)化(hua)膠的(de)(de)各項性能(neng)。常用(yong)的(de)(de)設備有開放式煉膠機(ji)(ji)、捏合機(ji)(ji)及真空密煉機(ji)(ji)。
主要性能
(1)高(gao)溫(wen)(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)顯(xian)著(zhu)的(de)(de)(de)(de)(de)特征是高(gao)溫(wen)(wen)(wen)(wen)(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing),雖然常(chang)溫(wen)(wen)(wen)(wen)(wen)下(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)(de)強度僅是天(tian)然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)或某些合成橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)(de)一半,但在(zai)200℃以(yi)上的(de)(de)(de)(de)(de)高(gao)溫(wen)(wen)(wen)(wen)(wen)環境下(xia),硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)(neng)(neng)保持一定的(de)(de)(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)和(he)表面(mian)硬度,且力學(xue)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)無(wu)(wu)明顯(xian)變化(hua)(hua)。(2)低溫(wen)(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)(de)玻璃化(hua)(hua)溫(wen)(wen)(wen)(wen)(wen)度一般為-70~-50℃,特殊配方(fang)可達-100℃,表明其低溫(wen)(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)優(you)異(yi)。這對航空、宇航工業的(de)(de)(de)(de)(de)意義(yi)重(zhong)大。(3)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵(jian)對氧(yang)(yang)(yang)、臭(chou)氧(yang)(yang)(yang)及紫(zi)外線等(deng)十(shi)分(fen)穩定,在(zai)不加(jia)任何添加(jia)劑的(de)(de)(de)(de)(de)情(qing)況下(xia),就具(ju)有(you)優(you)良的(de)(de)(de)(de)(de)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)(dian)(dian)氣性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)具(ju)有(you)優(you)異(yi)的(de)(de)(de)(de)(de)絕(jue)緣性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng),耐(nai)(nai)電(dian)(dian)(dian)暈性(xing)(xing)(xing)(xing)(xing)(xing)和(he)耐(nai)(nai)電(dian)(dian)(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)也非常(chang)好(hao)。(5)物(wu)(wu)理(li)機械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)常(chang)溫(wen)(wen)(wen)(wen)(wen)下(xia)的(de)(de)(de)(de)(de)物(wu)(wu)理(li)機械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)比通用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)差,但在(zai)150℃的(de)(de)(de)(de)(de)高(gao)溫(wen)(wen)(wen)(wen)(wen)和(he)-50℃的(de)(de)(de)(de)(de)低溫(wen)(wen)(wen)(wen)(wen)下(xia),其物(wu)(wu)理(li)機械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)優(you)于通用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)(nai)油及化(hua)(hua)學(xue)試劑性(xing)(xing)(xing)(xing)(xing)(xing)。普通硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)具(ju)有(you)中等(deng)的(de)(de)(de)(de)(de)耐(nai)(nai)油、耐(nai)(nai)溶(rong)劑性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。(7)氣體(ti)透過性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。室溫(wen)(wen)(wen)(wen)(wen)下(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)對空氣、氮、氧(yang)(yang)(yang)、二氧(yang)(yang)(yang)化(hua)(hua)碳(tan)等(deng)氣體(ti)的(de)(de)(de)(de)(de)透氣性(xing)(xing)(xing)(xing)(xing)(xing)比天(tian)然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)高(gao)出30-50倍。(8)生理(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)無(wu)(wu)毒,無(wu)(wu)味(wei),無(wu)(wu)嗅(xiu),與人體(ti)組(zu)織(zhi)(zhi)不粘連,具(ju)有(you)抗凝血(xue)作(zuo)用(yong)(yong),對肌(ji)體(ti)組(zu)織(zhi)(zhi)的(de)(de)(de)(de)(de)反(fan)應性(xing)(xing)(xing)(xing)(xing)(xing)非常(chang)少。特別適合作(zuo)為醫用(yong)(yong)材料。
硅橡膠的用量
據中國汽(qi)(qi)(qi)(qi)車(che)(che)工(gong)(gong)業(ye)協會(hui)統(tong)計,2012年(nian)(nian)(nian),汽(qi)(qi)(qi)(qi)車(che)(che)產(chan)銷分(fen)(fen)別(bie)達(da)到(dao)1927.18萬(wan)輛(liang)和(he)1930.64萬(wan)輛(liang),同比分(fen)(fen)別(bie)增長4.63%和(he)4.33%,汽(qi)(qi)(qi)(qi)車(che)(che)工(gong)(gong)業(ye)硅(gui)橡膠(jiao)的(de)(de)(de)用(yong)量(liang)約達(da)2.0萬(wan)t。根據觀研天下(xia)的(de)(de)(de)新研究,增加(jia)有機硅(gui)材料(liao)在汽(qi)(qi)(qi)(qi)車(che)(che)零(ling)(ling)部件方面的(de)(de)(de)用(yong)量(liang),可以大幅(fu)度(du)提高汽(qi)(qi)(qi)(qi)車(che)(che)的(de)(de)(de)安全性能,因此(ci),汽(qi)(qi)(qi)(qi)車(che)(che)產(chan)量(liang)和(he)單(dan)車(che)(che)用(yong)量(liang)水平的(de)(de)(de)提高都將(jiang)推動汽(qi)(qi)(qi)(qi)車(che)(che)工(gong)(gong)業(ye)對硅(gui)橡膠(jiao)需(xu)求(qiu)的(de)(de)(de)增加(jia)。國家(jia)鼓(gu)勵自主(zhu)(zhu)(zhu)品(pin)牌(pai)(pai)的(de)(de)(de)汽(qi)(qi)(qi)(qi)車(che)(che)發展(zhan),關鍵(jian)汽(qi)(qi)(qi)(qi)車(che)(che)零(ling)(ling)部件實現自主(zhu)(zhu)(zhu)化(hua),《2012年(nian)(nian)(nian)度(du)黨政(zheng)(zheng)機關公務(wu)用(yong)車(che)(che)選用(yong)車(che)(che)型目錄(lu)(征求(qiu)意(yi)見稿(gao))》為自主(zhu)(zhu)(zhu)品(pin)牌(pai)(pai)擴大在政(zheng)(zheng)府采(cai)購(gou)的(de)(de)(de)市場份額,為改變目前(qian)國內政(zheng)(zheng)府采(cai)購(gou)以合資品(pin)牌(pai)(pai)產(chan)品(pin)為主(zhu)(zhu)(zhu)的(de)(de)(de)局面提供(gong)(gong)了保障。促進自主(zhu)(zhu)(zhu)品(pin)牌(pai)(pai)發展(zhan),國產(chan)汽(qi)(qi)(qi)(qi)車(che)(che)業(ye)的(de)(de)(de)繁榮(rong)將(jiang)為汽(qi)(qi)(qi)(qi)車(che)(che)膠(jiao)的(de)(de)(de)應用(yong)提供(gong)(gong)有力保障。預測未來3年(nian)(nian)(nian),我國室溫(wen)硫化(hua)硅(gui)橡膠(jiao)在汽(qi)(qi)(qi)(qi)車(che)(che)行業(ye)將(jiang)以年(nian)(nian)(nian)均(jun)20%增長。
此外,硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)是(shi)重要的(de)(de)(de)非石(shi)(shi)油(you)基(ji)合成(cheng)橡(xiang)(xiang)(xiang)膠(jiao),約占(zhan)非石(shi)(shi)油(you)基(ji)合成(cheng)橡(xiang)(xiang)(xiang)膠(jiao)消費量的(de)(de)(de)98%。但(dan)因為(wei)石(shi)(shi)油(you)價格的(de)(de)(de)大(da)幅(fu)上漲(zhang),同(tong)時(shi)我(wo)國(guo)在硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)關鍵原料有(you)(you)機硅(gui)(gui)(gui)(gui)(gui)(gui)單(dan)體(ti)的(de)(de)(de)生(sheng)產(chan)(chan)技(ji)術(shu)方(fang)(fang)面(mian)取(qu)得突破(po),有(you)(you)機硅(gui)(gui)(gui)(gui)(gui)(gui)單(dan)體(ti)的(de)(de)(de)生(sheng)產(chan)(chan)技(ji)術(shu)在2005年前被幾家跨國(guo)公(gong)司壟(long)斷,但(dan)目前我(wo)國(guo)已發展成(cheng)為(wei)全球有(you)(you)機硅(gui)(gui)(gui)(gui)(gui)(gui)單(dan)體(ti)第(di)1大(da)國(guo),這(zhe)2個方(fang)(fang)面(mian)原因使(shi)硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)價格從2011年起開(kai)(kai)始低于石(shi)(shi)油(you)基(ji)合成(cheng)橡(xiang)(xiang)(xiang)膠(jiao),僅約為(wei)大(da)宗石(shi)(shi)油(you)基(ji)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)80%~90%,成(cheng)為(wei)廉價的(de)(de)(de)合成(cheng)橡(xiang)(xiang)(xiang)膠(jiao),并(bing)開(kai)(kai)始大(da)規模替代(dai)石(shi)(shi)油(you)基(ji)合成(cheng)橡(xiang)(xiang)(xiang)膠(jiao)。這(zhe)將極大(da)拓(tuo)展有(you)(you)機硅(gui)(gui)(gui)(gui)(gui)(gui)產(chan)(chan)業的(de)(de)(de)市場空間,同(tong)時(shi)將帶動(dong)硅(gui)(gui)(gui)(gui)(gui)(gui)油(you)、硅(gui)(gui)(gui)(gui)(gui)(gui)烷偶聯劑和硅(gui)(gui)(gui)(gui)(gui)(gui)樹(shu)脂(zhi)等其他有(you)(you)機硅(gui)(gui)(gui)(gui)(gui)(gui)產(chan)(chan)品的(de)(de)(de)消費。