
硅橡膠是(shi)指主鏈由硅(gui)(gui)和氧(yang)原子交替構成(cheng)(cheng),硅(gui)(gui)原子上通(tong)常連有兩個有機基(ji)團的橡(xiang)膠(jiao)。普(pu)通(tong)的硅(gui)(gui)橡(xiang)膠(jiao)主要由含甲基(ji)和少量(liang)乙烯基(ji)的硅(gui)(gui)氧(yang)鏈節組成(cheng)(cheng)。苯基(ji)的引入(ru)可(ke)提(ti)高(gao)硅(gui)(gui)橡(xiang)膠(jiao)的耐高(gao)、低(di)溫性(xing)(xing)能(neng)(neng),三氟丙基(ji)及氰基(ji)的引入(ru)則可(ke)提(ti)高(gao)硅(gui)(gui)橡(xiang)膠(jiao)的耐溫及耐油性(xing)(xing)能(neng)(neng)。硅(gui)(gui)橡(xiang)膠(jiao)耐低(di)溫性(xing)(xing)能(neng)(neng)良好,一般在-55℃下(xia)仍(reng)能(neng)(neng)工(gong)作(zuo)。引入(ru)苯基(ji)后,可(ke)達-73℃。硅(gui)(gui)橡(xiang)膠(jiao)的耐熱性(xing)(xing)能(neng)(neng)也(ye)很突出,在180℃下(xia)可(ke)長期工(gong)作(zuo),稍高(gao)于200℃也(ye)能(neng)(neng)承受數周或更長時間(jian)仍(reng)有彈(dan)性(xing)(xing),瞬時可(ke)耐300℃以上的高(gao)溫。硅(gui)(gui)橡(xiang)膠(jiao)的透氣性(xing)(xing)好,氧(yang)氣透過(guo)率在合成(cheng)(cheng)聚合物中是(shi)較高(gao)的。此外,硅(gui)(gui)橡(xiang)膠(jiao)還具有生(sheng)理惰性(xing)(xing)、不會(hui)導致凝(ning)血的突出特性(xing)(xing),因此在醫用領域(yu)應用廣(guang)泛(fan)。
主要品種
硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)分類的方法(fa)很多,通(tong)常按固(gu)化前的形態分為(wei)固(gu)體硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)和(he)(he)液(ye)體硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao);按硫化溫度分為(wei)室溫硫化硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao),高溫硫化硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao);按所用(yong)單體的不(bu)(bu)同(tong)(tong),可分為(wei)甲(jia)基(ji)乙烯(xi)基(ji)硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao),甲(jia)基(ji)苯基(ji)乙烯(xi)基(ji)硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)、氟硅(gui),腈硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)等(deng)(deng);按性能和(he)(he)用(yong)途的不(bu)(bu)同(tong)(tong)又可分為(wei)通(tong)用(yong)型(xing)(xing)(xing)、超耐(nai)低溫型(xing)(xing)(xing)、超耐(nai)高溫型(xing)(xing)(xing)、高強力(li)型(xing)(xing)(xing)、耐(nai)油型(xing)(xing)(xing)、醫(yi)用(yong)型(xing)(xing)(xing)等(deng)(deng)等(deng)(deng)。
發展史
硅(gui)(gui)橡(xiang)膠(jiao)早期(qi)是由美(mei)國(guo)(guo)以三氯化(hua)鐵為(wei)催化(hua)劑合成(cheng)的(de)(de)。1945年(nian)(nian),硅(gui)(gui)橡(xiang)膠(jiao)產品問世。1948年(nian)(nian),采用高比表面積的(de)(de)氣(qi)相法白炭(tan)黑補強的(de)(de)硅(gui)(gui)橡(xiang)膠(jiao)研制成(cheng)功(gong),使硅(gui)(gui)橡(xiang)膠(jiao)的(de)(de)性(xing)能躍升到實用階(jie)段,奠定(ding)了(le)現代(dai)硅(gui)(gui)橡(xiang)膠(jiao)生產技術(shu)的(de)(de)基礎。從二甲基二氯硅(gui)(gui)烷合成(cheng)開(kai)始生產硅(gui)(gui)橡(xiang)膠(jiao)的(de)(de)國(guo)(guo)家有美(mei)國(guo)(guo)。俄羅斯、德國(guo)(guo)、日(ri)本、韓國(guo)(guo)和中(zhong)國(guo)(guo)等(deng)。中(zhong)國(guo)(guo)硅(gui)(gui)橡(xiang)膠(jiao)的(de)(de)工業(ye)(ye)化(hua)研究(jiu)始于(yu)1957年(nian)(nian),多(duo)家研究(jiu)所和企業(ye)(ye)陸續開(kai)發出各(ge)種硅(gui)(gui)橡(xiang)膠(jiao)。到2003年(nian)(nian)底,中(zhong)國(guo)(guo)硅(gui)(gui)橡(xiang)膠(jiao)生產能力為(wei)135千(qian)噸(dun),其中(zhong)高溫膠(jiao)100千(qian)噸(dun)。
高溫硫化硅橡膠
高溫硫化(hua)硅(gui)橡膠(jiao)(jiao)(jiao)是指聚硅(gui)氧(yang)烷變成彈(dan)性(xing)(xing)(xing)體的(de)(de)過程是經(jing)過高溫(110-170℃)硫化(hua)成型的(de)(de)。它主要(yao)以高分子量的(de)(de)聚甲基(ji)乙烯(xi)基(ji)硅(gui)氧(yang)烷為(wei)生膠(jiao)(jiao)(jiao),混入(ru)補(bu)強填料、硫化(hua)劑等(deng),在加(jia)(jia)熱加(jia)(jia)壓下硫化(hua)成彈(dan)性(xing)(xing)(xing)體。硅(gui)橡膠(jiao)(jiao)(jiao)的(de)(de)補(bu)強主要(yao)是各種(zhong)(zhong)類型的(de)(de)白炭黑(hei),可使硫化(hua)膠(jiao)(jiao)(jiao)的(de)(de)強度增加(jia)(jia)數(shu)十(shi)倍(bei)。有時(shi)為(wei)了降低成本或改善膠(jiao)(jiao)(jiao)料性(xing)(xing)(xing)能(neng)及(ji)賦予硫化(hua)膠(jiao)(jiao)(jiao)各種(zhong)(zhong)特殊(shu)的(de)(de)性(xing)(xing)(xing)能(neng),也加(jia)(jia)入(ru)相應的(de)(de)各種(zhong)(zhong)添(tian)加(jia)(jia)劑。硫化(hua)劑是各種(zhong)(zhong)有機(ji)過氧(yang)化(hua)物或加(jia)(jia)成反應催化(hua)劑。
加工(gong)成型方法如(ru)圖所(suo)示。一次硫化的目(mu)(mu)的是進行(xing)高分子(zi)鏈的交(jiao)聯反(fan)應;二次硫化的目(mu)(mu)的是進行(xing)補充交(jiao)聯、驅除硫化劑分解(jie)產物(wu)和其他(ta)揮發性化合物(wu)以(yi)穩定硫化膠的各項性能。常用的設(she)備(bei)有開放式煉(lian)膠機(ji)(ji)、捏合機(ji)(ji)及(ji)真空密煉(lian)機(ji)(ji)。
主要性能
(1)高(gao)溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)顯(xian)著的(de)(de)(de)特(te)征是(shi)高(gao)溫(wen)(wen)(wen)(wen)穩定性(xing)(xing)(xing),雖然常溫(wen)(wen)(wen)(wen)下硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)強(qiang)度(du)僅是(shi)天(tian)然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)或某些(xie)合成橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)一(yi)半,但在(zai)(zai)200℃以上(shang)的(de)(de)(de)高(gao)溫(wen)(wen)(wen)(wen)環境下,硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)(neng)保持一(yi)定的(de)(de)(de)柔韌(ren)性(xing)(xing)(xing)、回彈(dan)性(xing)(xing)(xing)和(he)表(biao)面硬度(du),且力學性(xing)(xing)(xing)能(neng)(neng)(neng)(neng)無(wu)明(ming)顯(xian)變(bian)化(hua)(hua)(hua)。(2)低溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)能(neng)(neng)(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)玻璃(li)化(hua)(hua)(hua)溫(wen)(wen)(wen)(wen)度(du)一(yi)般(ban)為(wei)-70~-50℃,特(te)殊(shu)配方可(ke)達-100℃,表(biao)明(ming)其低溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優異(yi)。這對(dui)(dui)航(hang)空、宇航(hang)工業的(de)(de)(de)意義重大(da)。(3)耐(nai)(nai)候(hou)(hou)性(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵(jian)對(dui)(dui)氧、臭氧及紫外線等(deng)十分穩定,在(zai)(zai)不(bu)加(jia)任(ren)何添加(jia)劑(ji)的(de)(de)(de)情況下,就具有(you)優良(liang)的(de)(de)(de)耐(nai)(nai)候(hou)(hou)性(xing)(xing)(xing)。(4)電(dian)(dian)氣性(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)具有(you)優異(yi)的(de)(de)(de)絕緣性(xing)(xing)(xing)能(neng)(neng)(neng)(neng),耐(nai)(nai)電(dian)(dian)暈性(xing)(xing)(xing)和(he)耐(nai)(nai)電(dian)(dian)弧性(xing)(xing)(xing)也非(fei)常好。(5)物(wu)理(li)機械(xie)性(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)常溫(wen)(wen)(wen)(wen)下的(de)(de)(de)物(wu)理(li)機械(xie)性(xing)(xing)(xing)能(neng)(neng)(neng)(neng)比通(tong)(tong)用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)差(cha),但在(zai)(zai)150℃的(de)(de)(de)高(gao)溫(wen)(wen)(wen)(wen)和(he)-50℃的(de)(de)(de)低溫(wen)(wen)(wen)(wen)下,其物(wu)理(li)機械(xie)性(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優于(yu)通(tong)(tong)用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)(nai)油及化(hua)(hua)(hua)學試(shi)劑(ji)性(xing)(xing)(xing)。普通(tong)(tong)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)具有(you)中等(deng)的(de)(de)(de)耐(nai)(nai)油、耐(nai)(nai)溶劑(ji)性(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。(7)氣體(ti)透過性(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。室溫(wen)(wen)(wen)(wen)下硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)對(dui)(dui)空氣、氮、氧、二氧化(hua)(hua)(hua)碳(tan)等(deng)氣體(ti)的(de)(de)(de)透氣性(xing)(xing)(xing)比天(tian)然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)高(gao)出(chu)30-50倍(bei)。(8)生理(li)惰性(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)無(wu)毒(du),無(wu)味,無(wu)嗅,與人(ren)體(ti)組織不(bu)粘(zhan)連,具有(you)抗凝血作用(yong)(yong),對(dui)(dui)肌體(ti)組織的(de)(de)(de)反應性(xing)(xing)(xing)非(fei)常少。特(te)別適合作為(wei)醫用(yong)(yong)材料。
硅橡膠的用量
據中國汽(qi)(qi)(qi)車(che)(che)(che)(che)工(gong)業(ye)協會統計,2012年,汽(qi)(qi)(qi)車(che)(che)(che)(che)產(chan)(chan)銷(xiao)分(fen)別達(da)到(dao)1927.18萬(wan)(wan)輛和(he)1930.64萬(wan)(wan)輛,同比分(fen)別增長(chang)4.63%和(he)4.33%,汽(qi)(qi)(qi)車(che)(che)(che)(che)工(gong)業(ye)硅(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)用量約達(da)2.0萬(wan)(wan)t。根(gen)據觀(guan)研(yan)天(tian)下的(de)(de)新研(yan)究,增加有機(ji)(ji)硅(gui)材料在(zai)汽(qi)(qi)(qi)車(che)(che)(che)(che)零(ling)部件方面的(de)(de)用量,可以(yi)大幅度提高汽(qi)(qi)(qi)車(che)(che)(che)(che)的(de)(de)安全性能,因(yin)此,汽(qi)(qi)(qi)車(che)(che)(che)(che)產(chan)(chan)量和(he)單車(che)(che)(che)(che)用量水平的(de)(de)提高都將推動汽(qi)(qi)(qi)車(che)(che)(che)(che)工(gong)業(ye)對硅(gui)橡(xiang)膠(jiao)(jiao)需求的(de)(de)增加。國家鼓勵自主(zhu)(zhu)品(pin)(pin)牌(pai)(pai)的(de)(de)汽(qi)(qi)(qi)車(che)(che)(che)(che)發展(zhan),關(guan)鍵汽(qi)(qi)(qi)車(che)(che)(che)(che)零(ling)部件實現自主(zhu)(zhu)化(hua),《2012年度黨政(zheng)機(ji)(ji)關(guan)公務用車(che)(che)(che)(che)選用車(che)(che)(che)(che)型(xing)目錄(lu)(征(zheng)求意見稿)》為(wei)(wei)(wei)自主(zhu)(zhu)品(pin)(pin)牌(pai)(pai)擴大在(zai)政(zheng)府采購的(de)(de)市(shi)場份額(e),為(wei)(wei)(wei)改變目前國內政(zheng)府采購以(yi)合資品(pin)(pin)牌(pai)(pai)產(chan)(chan)品(pin)(pin)為(wei)(wei)(wei)主(zhu)(zhu)的(de)(de)局面提供了保障。促進(jin)自主(zhu)(zhu)品(pin)(pin)牌(pai)(pai)發展(zhan),國產(chan)(chan)汽(qi)(qi)(qi)車(che)(che)(che)(che)業(ye)的(de)(de)繁(fan)榮將為(wei)(wei)(wei)汽(qi)(qi)(qi)車(che)(che)(che)(che)膠(jiao)(jiao)的(de)(de)應用提供有力保障。預測未來3年,我國室(shi)溫硫化(hua)硅(gui)橡(xiang)膠(jiao)(jiao)在(zai)汽(qi)(qi)(qi)車(che)(che)(che)(che)行(xing)業(ye)將以(yi)年均20%增長(chang)。
此外(wai),硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)是重要的(de)(de)(de)非(fei)石(shi)(shi)油(you)(you)基(ji)合成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao),約占非(fei)石(shi)(shi)油(you)(you)基(ji)合成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)消費(fei)量的(de)(de)(de)98%。但因為石(shi)(shi)油(you)(you)價格(ge)的(de)(de)(de)大(da)幅上(shang)漲,同(tong)時我(wo)(wo)國(guo)(guo)在(zai)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)關鍵原料(liao)有(you)機(ji)(ji)硅(gui)(gui)(gui)(gui)單(dan)體(ti)(ti)的(de)(de)(de)生產技(ji)(ji)術方(fang)面(mian)取得突破,有(you)機(ji)(ji)硅(gui)(gui)(gui)(gui)單(dan)體(ti)(ti)的(de)(de)(de)生產技(ji)(ji)術在(zai)2005年前(qian)被幾家(jia)跨國(guo)(guo)公司壟斷,但目(mu)前(qian)我(wo)(wo)國(guo)(guo)已(yi)發(fa)展成(cheng)(cheng)為全球有(you)機(ji)(ji)硅(gui)(gui)(gui)(gui)單(dan)體(ti)(ti)第1大(da)國(guo)(guo),這2個方(fang)面(mian)原因使硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)價格(ge)從2011年起開始(shi)低于石(shi)(shi)油(you)(you)基(ji)合成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao),僅約為大(da)宗石(shi)(shi)油(you)(you)基(ji)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)80%~90%,成(cheng)(cheng)為廉價的(de)(de)(de)合成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao),并開始(shi)大(da)規(gui)模替代(dai)石(shi)(shi)油(you)(you)基(ji)合成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)。這將極(ji)大(da)拓展有(you)機(ji)(ji)硅(gui)(gui)(gui)(gui)產業(ye)的(de)(de)(de)市場(chang)空間,同(tong)時將帶動硅(gui)(gui)(gui)(gui)油(you)(you)、硅(gui)(gui)(gui)(gui)烷偶聯劑和硅(gui)(gui)(gui)(gui)樹脂等其(qi)他(ta)有(you)機(ji)(ji)硅(gui)(gui)(gui)(gui)產品的(de)(de)(de)消費(fei)。