
硅橡膠是(shi)指主鏈(lian)由硅(gui)(gui)和氧原子交替構成(cheng),硅(gui)(gui)原子上(shang)通(tong)常(chang)連有(you)(you)兩個有(you)(you)機基(ji)團的(de)(de)(de)(de)橡(xiang)(xiang)膠(jiao)。普通(tong)的(de)(de)(de)(de)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)主要由含(han)甲基(ji)和少量乙(yi)烯基(ji)的(de)(de)(de)(de)硅(gui)(gui)氧鏈(lian)節組成(cheng)。苯基(ji)的(de)(de)(de)(de)引入(ru)可(ke)提(ti)高(gao)(gao)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)耐(nai)(nai)高(gao)(gao)、低溫(wen)(wen)性(xing)能(neng)(neng)(neng)(neng),三氟丙基(ji)及氰基(ji)的(de)(de)(de)(de)引入(ru)則可(ke)提(ti)高(gao)(gao)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)耐(nai)(nai)溫(wen)(wen)及耐(nai)(nai)油性(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)耐(nai)(nai)低溫(wen)(wen)性(xing)能(neng)(neng)(neng)(neng)良好(hao),一般在(zai)-55℃下仍(reng)能(neng)(neng)(neng)(neng)工(gong)作。引入(ru)苯基(ji)后,可(ke)達-73℃。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)耐(nai)(nai)熱(re)性(xing)能(neng)(neng)(neng)(neng)也(ye)(ye)很突出,在(zai)180℃下可(ke)長期工(gong)作,稍高(gao)(gao)于200℃也(ye)(ye)能(neng)(neng)(neng)(neng)承(cheng)受數周(zhou)或(huo)更長時間(jian)仍(reng)有(you)(you)彈性(xing),瞬時可(ke)耐(nai)(nai)300℃以(yi)上(shang)的(de)(de)(de)(de)高(gao)(gao)溫(wen)(wen)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)透氣(qi)性(xing)好(hao),氧氣(qi)透過率在(zai)合(he)成(cheng)聚合(he)物(wu)中是(shi)較高(gao)(gao)的(de)(de)(de)(de)。此外,硅(gui)(gui)橡(xiang)(xiang)膠(jiao)還具(ju)有(you)(you)生理惰(duo)性(xing)、不(bu)會導致凝血的(de)(de)(de)(de)突出特性(xing),因此在(zai)醫(yi)用(yong)領(ling)域應(ying)用(yong)廣(guang)泛。
主要品種
硅(gui)(gui)橡(xiang)(xiang)膠分類的方(fang)法很多,通(tong)常按固化(hua)前的形態分為(wei)(wei)固體硅(gui)(gui)橡(xiang)(xiang)膠和液體硅(gui)(gui)橡(xiang)(xiang)膠;按硫化(hua)溫(wen)(wen)度分為(wei)(wei)室溫(wen)(wen)硫化(hua)硅(gui)(gui)橡(xiang)(xiang)膠,高溫(wen)(wen)硫化(hua)硅(gui)(gui)橡(xiang)(xiang)膠;按所用(yong)(yong)(yong)單體的不同,可分為(wei)(wei)甲基(ji)乙烯(xi)基(ji)硅(gui)(gui)橡(xiang)(xiang)膠,甲基(ji)苯基(ji)乙烯(xi)基(ji)硅(gui)(gui)橡(xiang)(xiang)膠、氟(fu)硅(gui)(gui),腈(jing)硅(gui)(gui)橡(xiang)(xiang)膠等(deng);按性能和用(yong)(yong)(yong)途的不同又(you)可分為(wei)(wei)通(tong)用(yong)(yong)(yong)型(xing)(xing)、超耐低溫(wen)(wen)型(xing)(xing)、超耐高溫(wen)(wen)型(xing)(xing)、高強力型(xing)(xing)、耐油型(xing)(xing)、醫用(yong)(yong)(yong)型(xing)(xing)等(deng)等(deng)。
發展史
硅橡(xiang)膠(jiao)(jiao)早期是由美(mei)國(guo)(guo)以(yi)三氯化(hua)(hua)鐵為(wei)催化(hua)(hua)劑合成(cheng)的。1945年(nian)(nian),硅橡(xiang)膠(jiao)(jiao)產品問世。1948年(nian)(nian),采用(yong)高(gao)比表面積的氣相法(fa)白炭黑(hei)補強的硅橡(xiang)膠(jiao)(jiao)研制成(cheng)功,使(shi)硅橡(xiang)膠(jiao)(jiao)的性能躍(yue)升到實(shi)用(yong)階段,奠定了現代硅橡(xiang)膠(jiao)(jiao)生產技術的基礎。從(cong)二(er)甲基二(er)氯硅烷(wan)合成(cheng)開始生產硅橡(xiang)膠(jiao)(jiao)的國(guo)(guo)家有(you)美(mei)國(guo)(guo)。俄羅斯、德國(guo)(guo)、日(ri)本、韓國(guo)(guo)和(he)中(zhong)(zhong)國(guo)(guo)等。中(zhong)(zhong)國(guo)(guo)硅橡(xiang)膠(jiao)(jiao)的工業化(hua)(hua)研究始于1957年(nian)(nian),多家研究所和(he)企業陸(lu)續開發出各種(zhong)硅橡(xiang)膠(jiao)(jiao)。到2003年(nian)(nian)底(di),中(zhong)(zhong)國(guo)(guo)硅橡(xiang)膠(jiao)(jiao)生產能力為(wei)135千(qian)噸,其中(zhong)(zhong)高(gao)溫膠(jiao)(jiao)100千(qian)噸。
高溫硫化硅橡膠
高(gao)溫硫(liu)(liu)(liu)化硅(gui)(gui)橡膠(jiao)(jiao)(jiao)是指聚(ju)硅(gui)(gui)氧(yang)烷變成(cheng)彈(dan)性(xing)體(ti)的(de)(de)過(guo)程(cheng)是經過(guo)高(gao)溫(110-170℃)硫(liu)(liu)(liu)化成(cheng)型的(de)(de)。它主要以高(gao)分子(zi)量的(de)(de)聚(ju)甲(jia)基乙(yi)烯(xi)基硅(gui)(gui)氧(yang)烷為(wei)生膠(jiao)(jiao)(jiao),混(hun)入補強填料、硫(liu)(liu)(liu)化劑(ji)(ji)等,在加(jia)熱加(jia)壓下(xia)硫(liu)(liu)(liu)化成(cheng)彈(dan)性(xing)體(ti)。硅(gui)(gui)橡膠(jiao)(jiao)(jiao)的(de)(de)補強主要是各(ge)種(zhong)類型的(de)(de)白(bai)炭黑(hei),可使硫(liu)(liu)(liu)化膠(jiao)(jiao)(jiao)的(de)(de)強度增加(jia)數十倍。有(you)時(shi)為(wei)了降低成(cheng)本或改(gai)善膠(jiao)(jiao)(jiao)料性(xing)能及賦予硫(liu)(liu)(liu)化膠(jiao)(jiao)(jiao)各(ge)種(zhong)特(te)殊的(de)(de)性(xing)能,也加(jia)入相應的(de)(de)各(ge)種(zhong)添加(jia)劑(ji)(ji)。硫(liu)(liu)(liu)化劑(ji)(ji)是各(ge)種(zhong)有(you)機過(guo)氧(yang)化物或加(jia)成(cheng)反(fan)應催(cui)化劑(ji)(ji)。
加工(gong)成型方法如(ru)圖(tu)所(suo)示。一次(ci)硫化(hua)(hua)(hua)的(de)目的(de)是(shi)進(jin)行高分子鏈的(de)交聯(lian)(lian)反應;二次(ci)硫化(hua)(hua)(hua)的(de)目的(de)是(shi)進(jin)行補(bu)充(chong)交聯(lian)(lian)、驅(qu)除硫化(hua)(hua)(hua)劑分解(jie)產物(wu)和(he)其他(ta)揮發性(xing)化(hua)(hua)(hua)合物(wu)以(yi)穩定硫化(hua)(hua)(hua)膠(jiao)的(de)各項性(xing)能。常用(yong)的(de)設(she)備有開放式煉(lian)膠(jiao)機(ji)、捏合機(ji)及真空密煉(lian)機(ji)。
主要性能
(1)高(gao)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)顯著的(de)(de)(de)(de)特征是高(gao)溫(wen)(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖(sui)然常(chang)(chang)(chang)溫(wen)(wen)下硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)強度僅是天(tian)然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)或某些合(he)(he)成橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)一(yi)半,但在200℃以上的(de)(de)(de)(de)高(gao)溫(wen)(wen)環境下,硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)保持一(yi)定的(de)(de)(de)(de)柔(rou)韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)表面(mian)硬度,且力學(xue)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)無(wu)明顯變化。(2)低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)玻璃(li)化溫(wen)(wen)度一(yi)般為-70~-50℃,特殊(shu)配方可達(da)-100℃,表明其低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)異。這(zhe)對(dui)(dui)航(hang)空、宇航(hang)工業(ye)的(de)(de)(de)(de)意義重大。(3)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵對(dui)(dui)氧(yang)、臭(chou)氧(yang)及(ji)紫(zi)外線等(deng)十分(fen)穩定,在不加任何添加劑的(de)(de)(de)(de)情況下,就具(ju)有優(you)良(liang)的(de)(de)(de)(de)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)有優(you)異的(de)(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng),耐(nai)電(dian)暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)耐(nai)電(dian)弧(hu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)也(ye)非常(chang)(chang)(chang)好。(5)物理(li)機(ji)械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)常(chang)(chang)(chang)溫(wen)(wen)下的(de)(de)(de)(de)物理(li)機(ji)械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)比通用橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)差(cha),但在150℃的(de)(de)(de)(de)高(gao)溫(wen)(wen)和(he)-50℃的(de)(de)(de)(de)低(di)溫(wen)(wen)下,其物理(li)機(ji)械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)于(yu)通用橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)油(you)及(ji)化學(xue)試劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)有中等(deng)的(de)(de)(de)(de)耐(nai)油(you)、耐(nai)溶劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。(7)氣(qi)(qi)體(ti)透過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。室溫(wen)(wen)下硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)對(dui)(dui)空氣(qi)(qi)、氮、氧(yang)、二氧(yang)化碳等(deng)氣(qi)(qi)體(ti)的(de)(de)(de)(de)透氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天(tian)然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)高(gao)出30-50倍。(8)生理(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)無(wu)毒,無(wu)味,無(wu)嗅,與人(ren)體(ti)組(zu)織不粘連,具(ju)有抗凝血作用,對(dui)(dui)肌體(ti)組(zu)織的(de)(de)(de)(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常(chang)(chang)(chang)少。特別適合(he)(he)作為醫用材料。
硅橡膠的用量
據中國(guo)(guo)(guo)汽(qi)(qi)車(che)(che)(che)工業(ye)協會統計,2012年,汽(qi)(qi)車(che)(che)(che)產(chan)(chan)銷分別(bie)(bie)達(da)(da)到1927.18萬輛(liang)(liang)和1930.64萬輛(liang)(liang),同比分別(bie)(bie)增(zeng)長(chang)4.63%和4.33%,汽(qi)(qi)車(che)(che)(che)工業(ye)硅橡膠(jiao)的用(yong)(yong)量(liang)約(yue)達(da)(da)2.0萬t。根(gen)據觀(guan)研天下(xia)的新研究,增(zeng)加(jia)有機硅材料在(zai)汽(qi)(qi)車(che)(che)(che)零(ling)部件(jian)方面的用(yong)(yong)量(liang),可以(yi)大幅度提高汽(qi)(qi)車(che)(che)(che)的安全性能,因此,汽(qi)(qi)車(che)(che)(che)產(chan)(chan)量(liang)和單車(che)(che)(che)用(yong)(yong)量(liang)水平的提高都將(jiang)推動(dong)汽(qi)(qi)車(che)(che)(che)工業(ye)對(dui)硅橡膠(jiao)需求(qiu)的增(zeng)加(jia)。國(guo)(guo)(guo)家(jia)鼓(gu)勵自主(zhu)(zhu)品牌(pai)的汽(qi)(qi)車(che)(che)(che)發展,關鍵汽(qi)(qi)車(che)(che)(che)零(ling)部件(jian)實(shi)現自主(zhu)(zhu)化(hua),《2012年度黨政(zheng)機關公務用(yong)(yong)車(che)(che)(che)選用(yong)(yong)車(che)(che)(che)型目錄(征求(qiu)意見稿)》為(wei)自主(zhu)(zhu)品牌(pai)擴大在(zai)政(zheng)府采購(gou)的市場份額(e),為(wei)改變目前(qian)國(guo)(guo)(guo)內(nei)政(zheng)府采購(gou)以(yi)合資品牌(pai)產(chan)(chan)品為(wei)主(zhu)(zhu)的局面提供(gong)了保障。促進自主(zhu)(zhu)品牌(pai)發展,國(guo)(guo)(guo)產(chan)(chan)汽(qi)(qi)車(che)(che)(che)業(ye)的繁(fan)榮(rong)將(jiang)為(wei)汽(qi)(qi)車(che)(che)(che)膠(jiao)的應用(yong)(yong)提供(gong)有力保障。預測未來3年,我國(guo)(guo)(guo)室(shi)溫硫(liu)化(hua)硅橡膠(jiao)在(zai)汽(qi)(qi)車(che)(che)(che)行業(ye)將(jiang)以(yi)年均20%增(zeng)長(chang)。
此外,硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)是重要的非石(shi)(shi)油(you)基(ji)(ji)合成橡(xiang)膠(jiao)(jiao),約占非石(shi)(shi)油(you)基(ji)(ji)合成橡(xiang)膠(jiao)(jiao)消費量的98%。但因為(wei)石(shi)(shi)油(you)價格的大幅上漲,同時我(wo)國在(zai)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的關鍵(jian)原料有(you)(you)(you)機(ji)(ji)(ji)硅(gui)(gui)(gui)(gui)(gui)單(dan)體的生產(chan)(chan)技術(shu)方面取得突破,有(you)(you)(you)機(ji)(ji)(ji)硅(gui)(gui)(gui)(gui)(gui)單(dan)體的生產(chan)(chan)技術(shu)在(zai)2005年前被幾家跨(kua)國公司壟(long)斷,但目前我(wo)國已發展成為(wei)全球有(you)(you)(you)機(ji)(ji)(ji)硅(gui)(gui)(gui)(gui)(gui)單(dan)體第1大國,這(zhe)(zhe)2個方面原因使硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的價格從2011年起開(kai)始(shi)低于石(shi)(shi)油(you)基(ji)(ji)合成橡(xiang)膠(jiao)(jiao),僅(jin)約為(wei)大宗石(shi)(shi)油(you)基(ji)(ji)橡(xiang)膠(jiao)(jiao)的80%~90%,成為(wei)廉(lian)價的合成橡(xiang)膠(jiao)(jiao),并開(kai)始(shi)大規模替代石(shi)(shi)油(you)基(ji)(ji)合成橡(xiang)膠(jiao)(jiao)。這(zhe)(zhe)將(jiang)極(ji)大拓(tuo)展有(you)(you)(you)機(ji)(ji)(ji)硅(gui)(gui)(gui)(gui)(gui)產(chan)(chan)業的市場空間,同時將(jiang)帶動(dong)硅(gui)(gui)(gui)(gui)(gui)油(you)、硅(gui)(gui)(gui)(gui)(gui)烷偶(ou)聯劑和硅(gui)(gui)(gui)(gui)(gui)樹脂等其他有(you)(you)(you)機(ji)(ji)(ji)硅(gui)(gui)(gui)(gui)(gui)產(chan)(chan)品的消費。