硅橡膠是指主鏈由硅(gui)(gui)(gui)和氧(yang)(yang)原子(zi)交替構(gou)成(cheng),硅(gui)(gui)(gui)原子(zi)上通常連(lian)有(you)兩個(ge)有(you)機基(ji)團(tuan)的(de)(de)(de)橡膠(jiao)。普通的(de)(de)(de)硅(gui)(gui)(gui)橡膠(jiao)主要由含甲基(ji)和少(shao)量乙烯基(ji)的(de)(de)(de)硅(gui)(gui)(gui)氧(yang)(yang)鏈節組成(cheng)。苯基(ji)的(de)(de)(de)引入可(ke)提高(gao)(gao)硅(gui)(gui)(gui)橡膠(jiao)的(de)(de)(de)耐高(gao)(gao)、低溫性(xing)能(neng),三氟丙(bing)基(ji)及氰基(ji)的(de)(de)(de)引入則可(ke)提高(gao)(gao)硅(gui)(gui)(gui)橡膠(jiao)的(de)(de)(de)耐溫及耐油性(xing)能(neng)。硅(gui)(gui)(gui)橡膠(jiao)耐低溫性(xing)能(neng)良好,一般(ban)在(zai)(zai)-55℃下(xia)仍能(neng)工作(zuo)(zuo)。引入苯基(ji)后,可(ke)達-73℃。硅(gui)(gui)(gui)橡膠(jiao)的(de)(de)(de)耐熱性(xing)能(neng)也(ye)很突(tu)出(chu),在(zai)(zai)180℃下(xia)可(ke)長期工作(zuo)(zuo),稍高(gao)(gao)于200℃也(ye)能(neng)承受數周或更長時間仍有(you)彈性(xing),瞬時可(ke)耐300℃以上的(de)(de)(de)高(gao)(gao)溫。硅(gui)(gui)(gui)橡膠(jiao)的(de)(de)(de)透(tou)氣(qi)(qi)性(xing)好,氧(yang)(yang)氣(qi)(qi)透(tou)過率在(zai)(zai)合(he)成(cheng)聚合(he)物中是較高(gao)(gao)的(de)(de)(de)。此外,硅(gui)(gui)(gui)橡膠(jiao)還具(ju)有(you)生理惰性(xing)、不會(hui)導致凝(ning)血的(de)(de)(de)突(tu)出(chu)特性(xing),因(yin)此在(zai)(zai)醫用領域應用廣泛。
主要品種
硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)分(fen)(fen)類的方法很多,通常(chang)按固(gu)化(hua)前的形(xing)態分(fen)(fen)為(wei)固(gu)體硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)和液體硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao);按硫化(hua)溫(wen)度分(fen)(fen)為(wei)室溫(wen)硫化(hua)硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao),高(gao)(gao)(gao)溫(wen)硫化(hua)硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao);按所用單體的不同(tong)(tong),可分(fen)(fen)為(wei)甲基(ji)乙烯基(ji)硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao),甲基(ji)苯基(ji)乙烯基(ji)硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)、氟硅,腈硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)等;按性能和用途(tu)的不同(tong)(tong)又可分(fen)(fen)為(wei)通用型(xing)(xing)、超耐低溫(wen)型(xing)(xing)、超耐高(gao)(gao)(gao)溫(wen)型(xing)(xing)、高(gao)(gao)(gao)強力(li)型(xing)(xing)、耐油型(xing)(xing)、醫用型(xing)(xing)等等。
發展史
硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)早期是(shi)由美(mei)國(guo)以三氯化鐵為催化劑(ji)合成(cheng)的(de)。1945年,硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)產(chan)(chan)品問世。1948年,采用(yong)高比表面積的(de)氣相法白炭黑補強的(de)硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)研制成(cheng)功,使(shi)硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)性能(neng)躍升(sheng)到實用(yong)階段,奠定了現代硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)生(sheng)產(chan)(chan)技術的(de)基礎。從二甲(jia)基二氯硅(gui)(gui)(gui)烷合成(cheng)開(kai)始生(sheng)產(chan)(chan)硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)國(guo)家有美(mei)國(guo)。俄(e)羅斯、德國(guo)、日本、韓國(guo)和(he)(he)中國(guo)等。中國(guo)硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)工業化研究(jiu)始于1957年,多家研究(jiu)所和(he)(he)企業陸(lu)續開(kai)發出各種(zhong)硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)。到2003年底,中國(guo)硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)生(sheng)產(chan)(chan)能(neng)力為135千(qian)(qian)噸(dun),其中高溫膠(jiao)100千(qian)(qian)噸(dun)。
高溫硫化硅橡膠
高溫(wen)硫(liu)化(hua)(hua)硅橡膠(jiao)是指聚(ju)硅氧(yang)烷(wan)變成彈性(xing)體的(de)(de)(de)(de)過程(cheng)是經過高溫(wen)(110-170℃)硫(liu)化(hua)(hua)成型的(de)(de)(de)(de)。它主(zhu)要以(yi)高分子量的(de)(de)(de)(de)聚(ju)甲基乙烯(xi)基硅氧(yang)烷(wan)為(wei)生膠(jiao),混入補(bu)強填料、硫(liu)化(hua)(hua)劑(ji)等,在加(jia)熱加(jia)壓下(xia)硫(liu)化(hua)(hua)成彈性(xing)體。硅橡膠(jiao)的(de)(de)(de)(de)補(bu)強主(zhu)要是各(ge)種(zhong)(zhong)類型的(de)(de)(de)(de)白炭黑,可使硫(liu)化(hua)(hua)膠(jiao)的(de)(de)(de)(de)強度增加(jia)數十倍。有(you)時為(wei)了(le)降低成本(ben)或改善膠(jiao)料性(xing)能及賦予(yu)硫(liu)化(hua)(hua)膠(jiao)各(ge)種(zhong)(zhong)特殊(shu)的(de)(de)(de)(de)性(xing)能,也加(jia)入相應的(de)(de)(de)(de)各(ge)種(zhong)(zhong)添加(jia)劑(ji)。硫(liu)化(hua)(hua)劑(ji)是各(ge)種(zhong)(zhong)有(you)機過氧(yang)化(hua)(hua)物或加(jia)成反應催化(hua)(hua)劑(ji)。
加(jia)工成(cheng)型方法(fa)如圖所示。一次硫化(hua)的(de)目(mu)(mu)的(de)是進行(xing)高分子鏈的(de)交聯(lian)反應;二次硫化(hua)的(de)目(mu)(mu)的(de)是進行(xing)補充交聯(lian)、驅除硫化(hua)劑分解(jie)產物(wu)和其(qi)他揮發性(xing)化(hua)合物(wu)以穩(wen)定(ding)硫化(hua)膠的(de)各項性(xing)能。常用的(de)設備有開放式(shi)煉膠機、捏合機及(ji)真空密(mi)煉機。
主要性能
(1)高溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)顯(xian)著的(de)(de)(de)特征是高溫(wen)(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然(ran)常溫(wen)(wen)下硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)強度(du)僅是天然(ran)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)或(huo)某(mou)些(xie)合成(cheng)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)一半,但在(zai)200℃以上(shang)的(de)(de)(de)高溫(wen)(wen)環境(jing)下,硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)仍能保(bao)持一定的(de)(de)(de)柔(rou)韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)表(biao)(biao)面硬度(du),且力學(xue)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能無明顯(xian)變(bian)化。(2)低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)玻璃化溫(wen)(wen)度(du)一般(ban)為-70~-50℃,特殊配(pei)方可達-100℃,表(biao)(biao)明其低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能優異。這對航空(kong)、宇航工業的(de)(de)(de)意義重(zhong)大。(3)耐(nai)(nai)(nai)(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)中Si-O-Si鍵對氧(yang)(yang)(yang)、臭氧(yang)(yang)(yang)及紫外(wai)線等(deng)十分(fen)穩定,在(zai)不加(jia)任何添加(jia)劑(ji)的(de)(de)(de)情況下,就具有優良的(de)(de)(de)耐(nai)(nai)(nai)(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)具有優異的(de)(de)(de)絕(jue)緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能,耐(nai)(nai)(nai)(nai)(nai)電(dian)暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)耐(nai)(nai)(nai)(nai)(nai)電(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非常好。(5)物(wu)(wu)理(li)(li)機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)常溫(wen)(wen)下的(de)(de)(de)物(wu)(wu)理(li)(li)機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能比(bi)(bi)通(tong)用橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)差,但在(zai)150℃的(de)(de)(de)高溫(wen)(wen)和(he)-50℃的(de)(de)(de)低(di)溫(wen)(wen)下,其物(wu)(wu)理(li)(li)機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能優于通(tong)用橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)。(6)耐(nai)(nai)(nai)(nai)(nai)油及化學(xue)試劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)具有中等(deng)的(de)(de)(de)耐(nai)(nai)(nai)(nai)(nai)油、耐(nai)(nai)(nai)(nai)(nai)溶劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能。(7)氣(qi)(qi)體(ti)透過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能。室溫(wen)(wen)下硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)對空(kong)氣(qi)(qi)、氮(dan)、氧(yang)(yang)(yang)、二氧(yang)(yang)(yang)化碳等(deng)氣(qi)(qi)體(ti)的(de)(de)(de)透氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比(bi)(bi)天然(ran)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)高出(chu)30-50倍。(8)生理(li)(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)無毒,無味(wei),無嗅,與(yu)人(ren)體(ti)組織(zhi)(zhi)不粘連,具有抗凝血作(zuo)用,對肌(ji)體(ti)組織(zhi)(zhi)的(de)(de)(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常少。特別(bie)適合作(zuo)為醫用材料。
硅橡膠的用量
據中(zhong)國汽(qi)(qi)車(che)工(gong)業(ye)協會統計,2012年,汽(qi)(qi)車(che)產(chan)銷(xiao)分別達到1927.18萬(wan)輛(liang)和1930.64萬(wan)輛(liang),同比分別增長4.63%和4.33%,汽(qi)(qi)車(che)工(gong)業(ye)硅(gui)橡(xiang)膠的(de)(de)用(yong)(yong)(yong)量(liang)約(yue)達2.0萬(wan)t。根據觀研天下的(de)(de)新研究,增加(jia)有(you)機硅(gui)材料在(zai)汽(qi)(qi)車(che)零部(bu)件(jian)方面的(de)(de)用(yong)(yong)(yong)量(liang),可以(yi)大幅度提高(gao)汽(qi)(qi)車(che)的(de)(de)安全(quan)性能,因此,汽(qi)(qi)車(che)產(chan)量(liang)和單車(che)用(yong)(yong)(yong)量(liang)水平的(de)(de)提高(gao)都將(jiang)推動(dong)汽(qi)(qi)車(che)工(gong)業(ye)對硅(gui)橡(xiang)膠需求(qiu)的(de)(de)增加(jia)。國家鼓(gu)勵自主(zhu)(zhu)品(pin)牌的(de)(de)汽(qi)(qi)車(che)發(fa)展,關鍵汽(qi)(qi)車(che)零部(bu)件(jian)實現自主(zhu)(zhu)化(hua),《2012年度黨政機關公務用(yong)(yong)(yong)車(che)選用(yong)(yong)(yong)車(che)型目錄(征求(qiu)意見稿)》為(wei)自主(zhu)(zhu)品(pin)牌擴(kuo)大在(zai)政府(fu)采(cai)購的(de)(de)市場(chang)份額,為(wei)改變目前(qian)國內(nei)政府(fu)采(cai)購以(yi)合資品(pin)牌產(chan)品(pin)為(wei)主(zhu)(zhu)的(de)(de)局面提供(gong)(gong)了保障(zhang)。促進自主(zhu)(zhu)品(pin)牌發(fa)展,國產(chan)汽(qi)(qi)車(che)業(ye)的(de)(de)繁榮將(jiang)為(wei)汽(qi)(qi)車(che)膠的(de)(de)應用(yong)(yong)(yong)提供(gong)(gong)有(you)力(li)保障(zhang)。預測未來3年,我國室(shi)溫硫化(hua)硅(gui)橡(xiang)膠在(zai)汽(qi)(qi)車(che)行(xing)業(ye)將(jiang)以(yi)年均20%增長。
此外,硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)是重(zhong)要的(de)非石油基合成(cheng)橡(xiang)膠(jiao)(jiao),約占非石油基合成(cheng)橡(xiang)膠(jiao)(jiao)消(xiao)費(fei)量的(de)98%。但因為(wei)石油價(jia)格(ge)(ge)的(de)大(da)(da)幅上漲,同(tong)時我國(guo)在硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)關鍵原(yuan)料有(you)(you)機硅(gui)(gui)(gui)單體的(de)生(sheng)產技術(shu)方(fang)面(mian)取得突(tu)破,有(you)(you)機硅(gui)(gui)(gui)單體的(de)生(sheng)產技術(shu)在2005年前被(bei)幾(ji)家(jia)跨國(guo)公司壟斷,但目(mu)前我國(guo)已發(fa)展(zhan)成(cheng)為(wei)全球有(you)(you)機硅(gui)(gui)(gui)單體第1大(da)(da)國(guo),這2個方(fang)面(mian)原(yuan)因使硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)價(jia)格(ge)(ge)從(cong)2011年起開始(shi)低于石油基合成(cheng)橡(xiang)膠(jiao)(jiao),僅約為(wei)大(da)(da)宗石油基橡(xiang)膠(jiao)(jiao)的(de)80%~90%,成(cheng)為(wei)廉價(jia)的(de)合成(cheng)橡(xiang)膠(jiao)(jiao),并(bing)開始(shi)大(da)(da)規(gui)模替代石油基合成(cheng)橡(xiang)膠(jiao)(jiao)。這將極大(da)(da)拓(tuo)展(zhan)有(you)(you)機硅(gui)(gui)(gui)產業的(de)市場空間,同(tong)時將帶動(dong)硅(gui)(gui)(gui)油、硅(gui)(gui)(gui)烷偶聯劑和硅(gui)(gui)(gui)樹脂等其他有(you)(you)機硅(gui)(gui)(gui)產品的(de)消(xiao)費(fei)。