
硅橡膠是指主(zhu)鏈由(you)硅(gui)(gui)(gui)和氧(yang)原(yuan)(yuan)子交替構成,硅(gui)(gui)(gui)原(yuan)(yuan)子上(shang)通(tong)常連(lian)有(you)(you)兩個有(you)(you)機基(ji)團(tuan)的(de)橡膠(jiao)(jiao)。普(pu)通(tong)的(de)硅(gui)(gui)(gui)橡膠(jiao)(jiao)主(zhu)要由(you)含甲基(ji)和少量(liang)乙(yi)烯基(ji)的(de)硅(gui)(gui)(gui)氧(yang)鏈節組成。苯基(ji)的(de)引(yin)入(ru)可提(ti)高(gao)硅(gui)(gui)(gui)橡膠(jiao)(jiao)的(de)耐(nai)(nai)高(gao)、低(di)溫性(xing)(xing)(xing)(xing)能,三氟丙基(ji)及氰基(ji)的(de)引(yin)入(ru)則(ze)可提(ti)高(gao)硅(gui)(gui)(gui)橡膠(jiao)(jiao)的(de)耐(nai)(nai)溫及耐(nai)(nai)油性(xing)(xing)(xing)(xing)能。硅(gui)(gui)(gui)橡膠(jiao)(jiao)耐(nai)(nai)低(di)溫性(xing)(xing)(xing)(xing)能良好(hao),一(yi)般在(zai)-55℃下(xia)仍(reng)(reng)能工(gong)作。引(yin)入(ru)苯基(ji)后,可達-73℃。硅(gui)(gui)(gui)橡膠(jiao)(jiao)的(de)耐(nai)(nai)熱性(xing)(xing)(xing)(xing)能也(ye)很突出(chu),在(zai)180℃下(xia)可長(chang)期工(gong)作,稍高(gao)于200℃也(ye)能承(cheng)受數周或更長(chang)時(shi)(shi)間仍(reng)(reng)有(you)(you)彈(dan)性(xing)(xing)(xing)(xing),瞬(shun)時(shi)(shi)可耐(nai)(nai)300℃以上(shang)的(de)高(gao)溫。硅(gui)(gui)(gui)橡膠(jiao)(jiao)的(de)透氣性(xing)(xing)(xing)(xing)好(hao),氧(yang)氣透過率在(zai)合成聚(ju)合物(wu)中是較高(gao)的(de)。此(ci)外,硅(gui)(gui)(gui)橡膠(jiao)(jiao)還具有(you)(you)生理惰性(xing)(xing)(xing)(xing)、不會導致凝血的(de)突出(chu)特性(xing)(xing)(xing)(xing),因此(ci)在(zai)醫用領域應用廣泛。
主要品種
硅橡膠(jiao)分類的(de)方法很多,通常按固(gu)化(hua)
前(qian)的形態分為固(gu)體(ti)硅(gui)橡(xiang)(xiang)膠(jiao)和液體(ti)硅(gui)橡(xiang)(xiang)膠(jiao);按硫化溫度分為室(shi)溫硫化硅(gui)橡(xiang)(xiang)膠(jiao),高溫硫化硅(gui)橡(xiang)(xiang)膠(jiao);按所用(yong)(yong)單體(ti)的不同,可分為甲(jia)基乙烯基硅(gui)橡(xiang)(xiang)膠(jiao),甲(jia)基苯基乙烯基硅(gui)橡(xiang)(xiang)膠(jiao)、氟(fu)硅(gui),腈(jing)硅(gui)橡(xiang)(xiang)膠(jiao)等(deng);按性能和用(yong)(yong)途的不同又可分為通用(yong)(yong)型、超耐低溫型、超耐高溫型、高強力型、耐油(you)型、醫用(yong)(yong)型等(deng)等(deng)。
發展(zhan)史
硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)早期是(shi)由美(mei)國(guo)(guo)以三(san)氯化鐵為(wei)催化劑合成的(de)(de)。1945年(nian)(nian),硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)產(chan)品(pin)問世。1948年(nian)(nian),采用(yong)高比(bi)表面積(ji)的(de)(de)氣(qi)相法白炭(tan)黑補強的(de)(de)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)研制成功,使硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)性能躍(yue)升到(dao)實(shi)用(yong)階段,奠定(ding)了(le)現代(dai)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)生(sheng)產(chan)技術的(de)(de)基(ji)礎。從二甲基(ji)二氯硅(gui)(gui)(gui)(gui)(gui)烷合成開(kai)始生(sheng)產(chan)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)國(guo)(guo)家有美(mei)國(guo)(guo)。俄羅斯(si)、德國(guo)(guo)、日(ri)本(ben)、韓國(guo)(guo)和中國(guo)(guo)等。中國(guo)(guo)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)工(gong)業(ye)化研究(jiu)始于1957年(nian)(nian),多家研究(jiu)所和企(qi)業(ye)陸(lu)續開(kai)發出各種硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)。到(dao)2003年(nian)(nian)底(di),中國(guo)(guo)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)生(sheng)產(chan)能力為(wei)135千噸,其中高溫膠(jiao)(jiao)(jiao)100千噸。
高溫硫化硅橡膠(jiao)
高(gao)溫硫(liu)(liu)(liu)(liu)化(hua)(hua)硅橡膠(jiao)是(shi)指聚硅氧(yang)烷(wan)變成彈(dan)性體的(de)過(guo)程是(shi)經過(guo)高(gao)溫(110-170℃)硫(liu)(liu)(liu)(liu)化(hua)(hua)成型(xing)的(de)。它(ta)主要(yao)以高(gao)分子量的(de)聚甲(jia)基乙烯基硅氧(yang)烷(wan)為生膠(jiao),混入(ru)補強(qiang)填料、硫(liu)(liu)(liu)(liu)化(hua)(hua)劑(ji)等,在加(jia)熱加(jia)壓下硫(liu)(liu)(liu)(liu)化(hua)(hua)成彈(dan)性體。硅橡膠(jiao)的(de)補強(qiang)主要(yao)是(shi)各(ge)種(zhong)(zhong)類型(xing)的(de)白炭黑,可(ke)使硫(liu)(liu)(liu)(liu)化(hua)(hua)膠(jiao)的(de)強(qiang)度(du)增加(jia)數十倍(bei)。有(you)時為了降低成本或改善膠(jiao)料性能及(ji)賦予(yu)硫(liu)(liu)(liu)(liu)化(hua)(hua)膠(jiao)各(ge)種(zhong)(zhong)特殊的(de)性能,也(ye)加(jia)入(ru)相應的(de)各(ge)種(zhong)(zhong)添加(jia)劑(ji)。硫(liu)(liu)(liu)(liu)化(hua)(hua)劑(ji)是(shi)各(ge)種(zhong)(zhong)有(you)機過(guo)氧(yang)化(hua)(hua)物或加(jia)成反應催化(hua)(hua)劑(ji)。
加工成型(xing)方(fang)法如圖所示。一(yi)次(ci)硫(liu)化(hua)的(de)(de)目的(de)(de)是進(jin)行(xing)高分子(zi)鏈的(de)(de)交聯(lian)(lian)反應;二次(ci)硫(liu)化(hua)的(de)(de)目的(de)(de)是進(jin)行(xing)補充(chong)交聯(lian)(lian)、驅除硫(liu)化(hua)劑分解產物和(he)其他揮發性化(hua)合(he)物以穩定硫(liu)化(hua)膠的(de)(de)各(ge)項性能。常用的(de)(de)設備有(you)開放(fang)式煉膠機(ji)、捏合(he)機(ji)及真空密(mi)煉機(ji)。
主要性能
(1)高溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)顯(xian)著的(de)(de)(de)(de)(de)(de)特征(zheng)是高溫(wen)(wen)穩定(ding)(ding)性(xing)(xing)(xing)(xing)(xing)(xing),雖然常(chang)溫(wen)(wen)下硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)(de)(de)強度(du)(du)僅是天(tian)然橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)或某些合成橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)(de)(de)一(yi)半,但在200℃以上的(de)(de)(de)(de)(de)(de)高溫(wen)(wen)環境下,硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)仍(reng)能(neng)(neng)(neng)保持一(yi)定(ding)(ding)的(de)(de)(de)(de)(de)(de)柔韌(ren)性(xing)(xing)(xing)(xing)(xing)(xing)、回彈(dan)性(xing)(xing)(xing)(xing)(xing)(xing)和表(biao)面硬(ying)度(du)(du),且力學(xue)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)無(wu)明顯(xian)變化(hua)。(2)低溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)(de)(de)玻璃化(hua)溫(wen)(wen)度(du)(du)一(yi)般為(wei)-70~-50℃,特殊配(pei)方可(ke)達-100℃,表(biao)明其(qi)低溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優異(yi)。這對航(hang)空、宇航(hang)工業(ye)的(de)(de)(de)(de)(de)(de)意義(yi)重大(da)。(3)耐(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)中(zhong)Si-O-Si鍵(jian)對氧、臭氧及紫(zi)外線等(deng)十分穩定(ding)(ding),在不(bu)加任何添加劑的(de)(de)(de)(de)(de)(de)情況下,就具(ju)有優良的(de)(de)(de)(de)(de)(de)耐(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)具(ju)有優異(yi)的(de)(de)(de)(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng),耐(nai)電(dian)暈性(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)電(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)也非(fei)常(chang)好。(5)物理(li)機(ji)(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)常(chang)溫(wen)(wen)下的(de)(de)(de)(de)(de)(de)物理(li)機(ji)(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)比通(tong)用(yong)(yong)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)差,但在150℃的(de)(de)(de)(de)(de)(de)高溫(wen)(wen)和-50℃的(de)(de)(de)(de)(de)(de)低溫(wen)(wen)下,其(qi)物理(li)機(ji)(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優于通(tong)用(yong)(yong)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)。(6)耐(nai)油及化(hua)學(xue)試劑性(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)具(ju)有中(zhong)等(deng)的(de)(de)(de)(de)(de)(de)耐(nai)油、耐(nai)溶劑性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。(7)氣體(ti)透過性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。室(shi)溫(wen)(wen)下硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)對空氣、氮、氧、二(er)氧化(hua)碳(tan)等(deng)氣體(ti)的(de)(de)(de)(de)(de)(de)透氣性(xing)(xing)(xing)(xing)(xing)(xing)比天(tian)然橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)高出30-50倍(bei)。(8)生理(li)惰(duo)性(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)無(wu)毒,無(wu)味,無(wu)嗅,與人(ren)體(ti)組織不(bu)粘連(lian),具(ju)有抗凝血(xue)作(zuo)用(yong)(yong),對肌體(ti)組織的(de)(de)(de)(de)(de)(de)反(fan)應性(xing)(xing)(xing)(xing)(xing)(xing)非(fei)常(chang)少。特別適合作(zuo)為(wei)醫用(yong)(yong)材(cai)料(liao)。
硅橡膠的用量
據(ju)(ju)中(zhong)國汽(qi)(qi)(qi)車(che)工業協會(hui)統計,2012年(nian),汽(qi)(qi)(qi)車(che)產銷分(fen)別達到1927.18萬輛和1930.64萬輛,同比分(fen)別增(zeng)長(chang)4.63%和4.33%,汽(qi)(qi)(qi)車(che)工業硅橡(xiang)膠的(de)(de)(de)用(yong)(yong)(yong)(yong)(yong)量(liang)(liang)約達2.0萬t。根(gen)據(ju)(ju)觀研天下的(de)(de)(de)新研究,增(zeng)加(jia)有(you)機硅材料在(zai)汽(qi)(qi)(qi)車(che)零部件(jian)方面的(de)(de)(de)用(yong)(yong)(yong)(yong)(yong)量(liang)(liang),可以大(da)幅度提(ti)高(gao)汽(qi)(qi)(qi)車(che)的(de)(de)(de)安全性能(neng),因此,汽(qi)(qi)(qi)車(che)產量(liang)(liang)和單車(che)用(yong)(yong)(yong)(yong)(yong)量(liang)(liang)水平的(de)(de)(de)提(ti)高(gao)都將推動汽(qi)(qi)(qi)車(che)工業對硅橡(xiang)膠需(xu)求的(de)(de)(de)增(zeng)加(jia)。國家鼓勵自主(zhu)品牌(pai)(pai)的(de)(de)(de)汽(qi)(qi)(qi)車(che)發(fa)展(zhan),關鍵汽(qi)(qi)(qi)車(che)零部件(jian)實現(xian)自主(zhu)化(hua),《2012年(nian)度黨(dang)政機關公(gong)務用(yong)(yong)(yong)(yong)(yong)車(che)選用(yong)(yong)(yong)(yong)(yong)車(che)型目(mu)錄(征求意見稿(gao))》為(wei)自主(zhu)品牌(pai)(pai)擴大(da)在(zai)政府采(cai)購的(de)(de)(de)市場份(fen)額,為(wei)改變目(mu)前(qian)國內(nei)政府采(cai)購以合資品牌(pai)(pai)產品為(wei)主(zhu)的(de)(de)(de)局(ju)面提(ti)供了保障。促(cu)進自主(zhu)品牌(pai)(pai)發(fa)展(zhan),國產汽(qi)(qi)(qi)車(che)業的(de)(de)(de)繁榮將為(wei)汽(qi)(qi)(qi)車(che)膠的(de)(de)(de)應用(yong)(yong)(yong)(yong)(yong)提(ti)供有(you)力保障。預(yu)測未來(lai)3年(nian),我國室溫硫(liu)化(hua)硅橡(xiang)膠在(zai)汽(qi)(qi)(qi)車(che)行業將以年(nian)均20%增(zeng)長(chang)。
此(ci)外,硅(gui)(gui)(gui)(gui)(gui)橡膠(jiao)(jiao)是重要的(de)(de)非石油(you)基合成(cheng)橡膠(jiao)(jiao),約(yue)(yue)占非石油(you)基合成(cheng)橡膠(jiao)(jiao)消費量(liang)的(de)(de)98%。但因為(wei)石油(you)價格(ge)的(de)(de)大(da)(da)幅上漲,同(tong)時(shi)我國在硅(gui)(gui)(gui)(gui)(gui)橡膠(jiao)(jiao)的(de)(de)關鍵原料有機(ji)(ji)硅(gui)(gui)(gui)(gui)(gui)單(dan)體的(de)(de)生(sheng)產(chan)技術方(fang)面取得突(tu)破,有機(ji)(ji)硅(gui)(gui)(gui)(gui)(gui)單(dan)體的(de)(de)生(sheng)產(chan)技術在2005年(nian)前(qian)(qian)被幾家跨國公(gong)司(si)壟斷(duan),但目(mu)前(qian)(qian)我國已發展(zhan)成(cheng)為(wei)全球有機(ji)(ji)硅(gui)(gui)(gui)(gui)(gui)單(dan)體第1大(da)(da)國,這2個方(fang)面原因使硅(gui)(gui)(gui)(gui)(gui)橡膠(jiao)(jiao)的(de)(de)價格(ge)從2011年(nian)起開始低于石油(you)基合成(cheng)橡膠(jiao)(jiao),僅約(yue)(yue)為(wei)大(da)(da)宗(zong)石油(you)基橡膠(jiao)(jiao)的(de)(de)80%~90%,成(cheng)為(wei)廉價的(de)(de)合成(cheng)橡膠(jiao)(jiao),并開始大(da)(da)規模替代石油(you)基合成(cheng)橡膠(jiao)(jiao)。這將極大(da)(da)拓(tuo)展(zhan)有機(ji)(ji)硅(gui)(gui)(gui)(gui)(gui)產(chan)業的(de)(de)市場空間,同(tong)時(shi)將帶動(dong)硅(gui)(gui)(gui)(gui)(gui)油(you)、硅(gui)(gui)(gui)(gui)(gui)烷偶聯劑和硅(gui)(gui)(gui)(gui)(gui)樹脂(zhi)等(deng)其他(ta)有機(ji)(ji)硅(gui)(gui)(gui)(gui)(gui)產(chan)品的(de)(de)消費。