
硅橡膠是(shi)指主鏈由硅和氧原子交替構(gou)成,硅原子上通(tong)常連(lian)有兩個有機基(ji)團(tuan)的(de)(de)橡(xiang)膠(jiao)(jiao)(jiao)。普通(tong)的(de)(de)硅橡(xiang)膠(jiao)(jiao)(jiao)主要由含甲基(ji)和少量乙烯基(ji)的(de)(de)硅氧鏈節組成。苯基(ji)的(de)(de)引入(ru)可(ke)(ke)提高(gao)硅橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)耐(nai)高(gao)、低(di)溫(wen)(wen)(wen)性(xing)(xing)(xing)能(neng)(neng)(neng),三氟丙基(ji)及(ji)氰(qing)基(ji)的(de)(de)引入(ru)則(ze)可(ke)(ke)提高(gao)硅橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)耐(nai)溫(wen)(wen)(wen)及(ji)耐(nai)油性(xing)(xing)(xing)能(neng)(neng)(neng)。硅橡(xiang)膠(jiao)(jiao)(jiao)耐(nai)低(di)溫(wen)(wen)(wen)性(xing)(xing)(xing)能(neng)(neng)(neng)良(liang)好(hao),一般在-55℃下(xia)仍(reng)能(neng)(neng)(neng)工作。引入(ru)苯基(ji)后,可(ke)(ke)達(da)-73℃。硅橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)耐(nai)熱(re)性(xing)(xing)(xing)能(neng)(neng)(neng)也很突(tu)出,在180℃下(xia)可(ke)(ke)長(chang)期工作,稍(shao)高(gao)于(yu)200℃也能(neng)(neng)(neng)承受數周或更長(chang)時(shi)間仍(reng)有彈性(xing)(xing)(xing),瞬時(shi)可(ke)(ke)耐(nai)300℃以上的(de)(de)高(gao)溫(wen)(wen)(wen)。硅橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)透(tou)氣性(xing)(xing)(xing)好(hao),氧氣透(tou)過率在合(he)成聚合(he)物中是(shi)較高(gao)的(de)(de)。此(ci)外(wai),硅橡(xiang)膠(jiao)(jiao)(jiao)還具有生理惰性(xing)(xing)(xing)、不會(hui)導致(zhi)凝血(xue)的(de)(de)突(tu)出特性(xing)(xing)(xing),因此(ci)在醫用領域應用廣泛。
主要品種
硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)分(fen)(fen)類(lei)的方(fang)法(fa)很多,通(tong)常按固化前的形態分(fen)(fen)為(wei)(wei)固體(ti)(ti)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)和(he)液體(ti)(ti)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao);按硫(liu)(liu)化溫度分(fen)(fen)為(wei)(wei)室溫硫(liu)(liu)化硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao),高(gao)溫硫(liu)(liu)化硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao);按所用(yong)(yong)單(dan)體(ti)(ti)的不同(tong),可(ke)分(fen)(fen)為(wei)(wei)甲基乙烯基硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao),甲基苯基乙烯基硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)、氟(fu)硅(gui)(gui),腈(jing)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)等(deng);按性能和(he)用(yong)(yong)途的不同(tong)又(you)可(ke)分(fen)(fen)為(wei)(wei)通(tong)用(yong)(yong)型(xing)、超耐(nai)低溫型(xing)、超耐(nai)高(gao)溫型(xing)、高(gao)強(qiang)力型(xing)、耐(nai)油型(xing)、醫用(yong)(yong)型(xing)等(deng)等(deng)。
發展史
硅(gui)(gui)橡膠(jiao)早期(qi)是由(you)美國(guo)以三氯(lv)化鐵為催化劑合(he)成(cheng)的。1945年,硅(gui)(gui)橡膠(jiao)產品問世。1948年,采用(yong)高比表面積(ji)的氣相法白炭黑補強的硅(gui)(gui)橡膠(jiao)研(yan)制成(cheng)功,使硅(gui)(gui)橡膠(jiao)的性能躍升到實用(yong)階(jie)段,奠定了現代(dai)硅(gui)(gui)橡膠(jiao)生產技(ji)術(shu)的基礎。從二甲基二氯(lv)硅(gui)(gui)烷合(he)成(cheng)開始(shi)(shi)生產硅(gui)(gui)橡膠(jiao)的國(guo)家有美國(guo)。俄羅斯、德(de)國(guo)、日本(ben)、韓國(guo)和(he)(he)中(zhong)國(guo)等。中(zhong)國(guo)硅(gui)(gui)橡膠(jiao)的工業化研(yan)究始(shi)(shi)于1957年,多家研(yan)究所和(he)(he)企(qi)業陸續開發(fa)出(chu)各種硅(gui)(gui)橡膠(jiao)。到2003年底,中(zhong)國(guo)硅(gui)(gui)橡膠(jiao)生產能力(li)為135千(qian)(qian)噸,其中(zhong)高溫膠(jiao)100千(qian)(qian)噸。
高溫硫化硅橡膠
高溫(wen)硫(liu)(liu)化(hua)硅橡膠(jiao)(jiao)是(shi)(shi)指聚硅氧(yang)烷變成(cheng)彈(dan)性(xing)(xing)體的過(guo)程是(shi)(shi)經過(guo)高溫(wen)(110-170℃)硫(liu)(liu)化(hua)成(cheng)型的。它主要以(yi)高分(fen)子量的聚甲基(ji)乙烯(xi)基(ji)硅氧(yang)烷為生膠(jiao)(jiao),混(hun)入補(bu)強(qiang)填料(liao)、硫(liu)(liu)化(hua)劑等,在(zai)加(jia)(jia)熱加(jia)(jia)壓下硫(liu)(liu)化(hua)成(cheng)彈(dan)性(xing)(xing)體。硅橡膠(jiao)(jiao)的補(bu)強(qiang)主要是(shi)(shi)各種類型的白炭黑(hei),可(ke)使硫(liu)(liu)化(hua)膠(jiao)(jiao)的強(qiang)度增加(jia)(jia)數十倍(bei)。有(you)時為了(le)降(jiang)低成(cheng)本或改善膠(jiao)(jiao)料(liao)性(xing)(xing)能及賦予(yu)硫(liu)(liu)化(hua)膠(jiao)(jiao)各種特殊(shu)的性(xing)(xing)能,也加(jia)(jia)入相應(ying)的各種添加(jia)(jia)劑。硫(liu)(liu)化(hua)劑是(shi)(shi)各種有(you)機過(guo)氧(yang)化(hua)物或加(jia)(jia)成(cheng)反(fan)應(ying)催化(hua)劑。
加工(gong)成型方法如圖(tu)所(suo)示。一(yi)次(ci)硫(liu)化的(de)(de)目的(de)(de)是進行高分子鏈的(de)(de)交(jiao)聯反(fan)應;二(er)次(ci)硫(liu)化的(de)(de)目的(de)(de)是進行補充交(jiao)聯、驅除硫(liu)化劑分解產物和其他(ta)揮發性化合物以穩定硫(liu)化膠的(de)(de)各項性能(neng)。常用(yong)的(de)(de)設備有開放式(shi)煉(lian)膠機、捏合機及真空密煉(lian)機。
主要性能
(1)高(gao)溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)顯(xian)著的(de)(de)(de)(de)(de)特(te)征是(shi)(shi)高(gao)溫(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然常(chang)(chang)溫(wen)下(xia)(xia)硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)(de)強(qiang)度(du)僅是(shi)(shi)天然橡(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(dan)(dan)在(zai)200℃以上的(de)(de)(de)(de)(de)高(gao)溫(wen)環(huan)境下(xia)(xia),硅橡(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)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)表(biao)面(mian)硬度(du),且力學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)無(wu)明(ming)顯(xian)變化(hua)。(2)低(di)溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)(de)玻璃化(hua)溫(wen)度(du)一般為-70~-50℃,特(te)殊(shu)配方可(ke)達-100℃,表(biao)明(ming)其低(di)溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)優異。這對(dui)航空、宇航工業(ye)的(de)(de)(de)(de)(de)意(yi)義(yi)重大。(3)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵對(dui)氧、臭氧及紫外線等十(shi)分(fen)穩定,在(zai)不加(jia)任(ren)何添加(jia)劑(ji)的(de)(de)(de)(de)(de)情況(kuang)下(xia)(xia),就(jiu)具(ju)(ju)(ju)有優良的(de)(de)(de)(de)(de)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)具(ju)(ju)(ju)有優異的(de)(de)(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng),耐(nai)(nai)電(dian)暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)耐(nai)(nai)電(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非常(chang)(chang)好。(5)物理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)常(chang)(chang)溫(wen)下(xia)(xia)的(de)(de)(de)(de)(de)物理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)比(bi)通(tong)用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)差,但(dan)(dan)在(zai)150℃的(de)(de)(de)(de)(de)高(gao)溫(wen)和(he)-50℃的(de)(de)(de)(de)(de)低(di)溫(wen)下(xia)(xia),其物理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)優于通(tong)用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)(nai)油及化(hua)學試(shi)劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)具(ju)(ju)(ju)有中等的(de)(de)(de)(de)(de)耐(nai)(nai)油、耐(nai)(nai)溶劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。(7)氣(qi)體(ti)(ti)透(tou)過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。室溫(wen)下(xia)(xia)硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)對(dui)空氣(qi)、氮、氧、二氧化(hua)碳等氣(qi)體(ti)(ti)的(de)(de)(de)(de)(de)透(tou)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比(bi)天然橡(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)(xing)(xing)。硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)無(wu)毒,無(wu)味,無(wu)嗅,與人體(ti)(ti)組織(zhi)(zhi)不粘連(lian),具(ju)(ju)(ju)有抗凝血作用(yong)(yong),對(dui)肌體(ti)(ti)組織(zhi)(zhi)的(de)(de)(de)(de)(de)反應(ying)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常(chang)(chang)少。特(te)別適合作為醫(yi)用(yong)(yong)材料(liao)。
硅橡膠的用量
據中國汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)工(gong)(gong)業協(xie)會統計(ji),2012年(nian),汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)產(chan)(chan)銷分(fen)別達到1927.18萬輛和1930.64萬輛,同(tong)比(bi)分(fen)別增長4.63%和4.33%,汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)工(gong)(gong)業硅(gui)橡(xiang)膠的(de)(de)用量(liang)約達2.0萬t。根據觀研天下的(de)(de)新研究,增加有(you)機硅(gui)材料在(zai)(zai)汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)零部件方面的(de)(de)用量(liang),可以(yi)大幅度提(ti)高汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)的(de)(de)安全(quan)性能,因此,汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)產(chan)(chan)量(liang)和單車(che)(che)(che)(che)用量(liang)水平的(de)(de)提(ti)高都(dou)將(jiang)推動汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)工(gong)(gong)業對硅(gui)橡(xiang)膠需求(qiu)的(de)(de)增加。國家鼓勵自(zi)主品(pin)(pin)牌(pai)的(de)(de)汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)發(fa)展,關(guan)(guan)鍵汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)零部件實現(xian)自(zi)主化(hua),《2012年(nian)度黨政(zheng)機關(guan)(guan)公務用車(che)(che)(che)(che)選用車(che)(che)(che)(che)型(xing)目(mu)錄(lu)(征求(qiu)意(yi)見稿(gao))》為(wei)自(zi)主品(pin)(pin)牌(pai)擴大在(zai)(zai)政(zheng)府采(cai)購(gou)的(de)(de)市場份額,為(wei)改變(bian)目(mu)前(qian)國內政(zheng)府采(cai)購(gou)以(yi)合資品(pin)(pin)牌(pai)產(chan)(chan)品(pin)(pin)為(wei)主的(de)(de)局面提(ti)供了保障。促進(jin)自(zi)主品(pin)(pin)牌(pai)發(fa)展,國產(chan)(chan)汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)業的(de)(de)繁榮將(jiang)為(wei)汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)膠的(de)(de)應(ying)用提(ti)供有(you)力保障。預(yu)測未來3年(nian),我國室溫硫化(hua)硅(gui)橡(xiang)膠在(zai)(zai)汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)行業將(jiang)以(yi)年(nian)均20%增長。
此外,硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)是重要(yao)的(de)(de)(de)非石(shi)(shi)油基(ji)(ji)合(he)成橡(xiang)(xiang)膠(jiao)(jiao),約占非石(shi)(shi)油基(ji)(ji)合(he)成橡(xiang)(xiang)膠(jiao)(jiao)消費量(liang)的(de)(de)(de)98%。但(dan)因為(wei)石(shi)(shi)油價(jia)格(ge)的(de)(de)(de)大(da)(da)幅(fu)上漲(zhang),同(tong)時我(wo)國在硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)關鍵原(yuan)料有(you)(you)機(ji)硅(gui)(gui)單體的(de)(de)(de)生(sheng)產(chan)技術方面(mian)取得突破,有(you)(you)機(ji)硅(gui)(gui)單體的(de)(de)(de)生(sheng)產(chan)技術在2005年(nian)前被(bei)幾家跨國公司(si)壟(long)斷,但(dan)目前我(wo)國已發展成為(wei)全球有(you)(you)機(ji)硅(gui)(gui)單體第(di)1大(da)(da)國,這(zhe)(zhe)2個方面(mian)原(yuan)因使硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)價(jia)格(ge)從2011年(nian)起(qi)開始低于(yu)石(shi)(shi)油基(ji)(ji)合(he)成橡(xiang)(xiang)膠(jiao)(jiao),僅約為(wei)大(da)(da)宗石(shi)(shi)油基(ji)(ji)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)80%~90%,成為(wei)廉價(jia)的(de)(de)(de)合(he)成橡(xiang)(xiang)膠(jiao)(jiao),并(bing)開始大(da)(da)規模替代石(shi)(shi)油基(ji)(ji)合(he)成橡(xiang)(xiang)膠(jiao)(jiao)。這(zhe)(zhe)將極大(da)(da)拓展有(you)(you)機(ji)硅(gui)(gui)產(chan)業的(de)(de)(de)市場空間,同(tong)時將帶動硅(gui)(gui)油、硅(gui)(gui)烷偶(ou)聯劑和硅(gui)(gui)樹(shu)脂等其(qi)他有(you)(you)機(ji)硅(gui)(gui)產(chan)品的(de)(de)(de)消費。