硅橡膠是指主(zhu)(zhu)鏈(lian)由(you)硅(gui)(gui)(gui)和氧(yang)原子交替構成,硅(gui)(gui)(gui)原子上通(tong)常連(lian)有兩個有機(ji)基(ji)團的(de)(de)(de)(de)橡(xiang)(xiang)膠。普通(tong)的(de)(de)(de)(de)硅(gui)(gui)(gui)橡(xiang)(xiang)膠主(zhu)(zhu)要由(you)含甲基(ji)和少量乙烯基(ji)的(de)(de)(de)(de)硅(gui)(gui)(gui)氧(yang)鏈(lian)節組成。苯(ben)基(ji)的(de)(de)(de)(de)引入可(ke)(ke)提高(gao)(gao)硅(gui)(gui)(gui)橡(xiang)(xiang)膠的(de)(de)(de)(de)耐(nai)高(gao)(gao)、低溫性(xing)能(neng)(neng),三氟(fu)丙基(ji)及氰(qing)基(ji)的(de)(de)(de)(de)引入則可(ke)(ke)提高(gao)(gao)硅(gui)(gui)(gui)橡(xiang)(xiang)膠的(de)(de)(de)(de)耐(nai)溫及耐(nai)油(you)性(xing)能(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)膠耐(nai)低溫性(xing)能(neng)(neng)良好,一般在(zai)-55℃下仍(reng)能(neng)(neng)工作。引入苯(ben)基(ji)后,可(ke)(ke)達(da)-73℃。硅(gui)(gui)(gui)橡(xiang)(xiang)膠的(de)(de)(de)(de)耐(nai)熱性(xing)能(neng)(neng)也很突出(chu),在(zai)180℃下可(ke)(ke)長期工作,稍高(gao)(gao)于200℃也能(neng)(neng)承(cheng)受數(shu)周或更長時間(jian)仍(reng)有彈性(xing),瞬時可(ke)(ke)耐(nai)300℃以(yi)上的(de)(de)(de)(de)高(gao)(gao)溫。硅(gui)(gui)(gui)橡(xiang)(xiang)膠的(de)(de)(de)(de)透氣性(xing)好,氧(yang)氣透過(guo)率在(zai)合(he)成聚合(he)物中是較高(gao)(gao)的(de)(de)(de)(de)。此外,硅(gui)(gui)(gui)橡(xiang)(xiang)膠還(huan)具有生理惰性(xing)、不會導致凝血的(de)(de)(de)(de)突出(chu)特性(xing),因此在(zai)醫用領域應用廣泛。
主要品種
硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)分(fen)類的(de)(de)方法很(hen)多(duo),通常按(an)(an)固(gu)化(hua)前的(de)(de)形(xing)態分(fen)為固(gu)體(ti)(ti)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)和液體(ti)(ti)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao);按(an)(an)硫(liu)化(hua)溫(wen)度分(fen)為室(shi)溫(wen)硫(liu)化(hua)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao),高溫(wen)硫(liu)化(hua)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao);按(an)(an)所用單體(ti)(ti)的(de)(de)不同,可分(fen)為甲基(ji)(ji)乙(yi)烯基(ji)(ji)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao),甲基(ji)(ji)苯基(ji)(ji)乙(yi)烯基(ji)(ji)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)、氟(fu)硅(gui)(gui),腈硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)等(deng);按(an)(an)性能和用途的(de)(de)不同又可分(fen)為通用型(xing)、超(chao)耐(nai)(nai)低溫(wen)型(xing)、超(chao)耐(nai)(nai)高溫(wen)型(xing)、高強力型(xing)、耐(nai)(nai)油型(xing)、醫(yi)用型(xing)等(deng)等(deng)。
發展史
硅(gui)(gui)橡膠(jiao)(jiao)早期(qi)是由美國(guo)以三(san)氯化(hua)鐵為催化(hua)劑合(he)成的(de)(de)。1945年(nian),硅(gui)(gui)橡膠(jiao)(jiao)產(chan)品問世。1948年(nian),采用高比表面(mian)積的(de)(de)氣相法(fa)白炭黑補強的(de)(de)硅(gui)(gui)橡膠(jiao)(jiao)研制成功(gong),使硅(gui)(gui)橡膠(jiao)(jiao)的(de)(de)性能躍升到(dao)實用階(jie)段(duan),奠定了(le)現代硅(gui)(gui)橡膠(jiao)(jiao)生產(chan)技(ji)術的(de)(de)基(ji)礎。從(cong)二甲基(ji)二氯硅(gui)(gui)烷合(he)成開始生產(chan)硅(gui)(gui)橡膠(jiao)(jiao)的(de)(de)國(guo)家(jia)有(you)美國(guo)。俄羅斯、德國(guo)、日本、韓國(guo)和中(zhong)國(guo)等。中(zhong)國(guo)硅(gui)(gui)橡膠(jiao)(jiao)的(de)(de)工業化(hua)研究(jiu)始于1957年(nian),多家(jia)研究(jiu)所和企業陸(lu)續開發出各(ge)種(zhong)硅(gui)(gui)橡膠(jiao)(jiao)。到(dao)2003年(nian)底,中(zhong)國(guo)硅(gui)(gui)橡膠(jiao)(jiao)生產(chan)能力為135千噸(dun),其中(zhong)高溫膠(jiao)(jiao)100千噸(dun)。
高溫硫化硅橡膠
高(gao)溫(wen)(wen)硫化(hua)(hua)(hua)(hua)(hua)硅(gui)橡(xiang)(xiang)膠(jiao)是(shi)(shi)指聚(ju)硅(gui)氧烷變成彈性(xing)體(ti)的過程是(shi)(shi)經過高(gao)溫(wen)(wen)(110-170℃)硫化(hua)(hua)(hua)(hua)(hua)成型(xing)的。它主要以高(gao)分子量的聚(ju)甲基乙烯基硅(gui)氧烷為生(sheng)膠(jiao),混入(ru)(ru)補(bu)強(qiang)(qiang)填料、硫化(hua)(hua)(hua)(hua)(hua)劑等(deng),在加(jia)熱加(jia)壓下(xia)硫化(hua)(hua)(hua)(hua)(hua)成彈性(xing)體(ti)。硅(gui)橡(xiang)(xiang)膠(jiao)的補(bu)強(qiang)(qiang)主要是(shi)(shi)各種類(lei)型(xing)的白炭黑(hei),可使(shi)硫化(hua)(hua)(hua)(hua)(hua)膠(jiao)的強(qiang)(qiang)度(du)增加(jia)數十倍。有時為了降低成本或改善膠(jiao)料性(xing)能及(ji)賦予硫化(hua)(hua)(hua)(hua)(hua)膠(jiao)各種特殊的性(xing)能,也加(jia)入(ru)(ru)相(xiang)應的各種添加(jia)劑。硫化(hua)(hua)(hua)(hua)(hua)劑是(shi)(shi)各種有機(ji)過氧化(hua)(hua)(hua)(hua)(hua)物(wu)或加(jia)成反應催(cui)化(hua)(hua)(hua)(hua)(hua)劑。
加(jia)工成型方(fang)法如圖所示(shi)。一次硫(liu)化(hua)的(de)目的(de)是(shi)進(jin)行高分(fen)子鏈的(de)交聯(lian)反(fan)應;二次硫(liu)化(hua)的(de)目的(de)是(shi)進(jin)行補充交聯(lian)、驅除硫(liu)化(hua)劑分(fen)解產物(wu)和其他揮(hui)發性(xing)化(hua)合(he)物(wu)以穩定硫(liu)化(hua)膠(jiao)的(de)各項(xiang)性(xing)能。常用的(de)設備有(you)開放(fang)式(shi)煉膠(jiao)機、捏合(he)機及(ji)真(zhen)空密煉機。
主要性能
(1)高(gao)(gao)溫(wen)(wen)(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)。硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)顯(xian)著(zhu)的(de)(de)(de)特(te)征是(shi)(shi)高(gao)(gao)溫(wen)(wen)(wen)(wen)(wen)(wen)穩(wen)定(ding)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然(ran)常(chang)溫(wen)(wen)(wen)(wen)(wen)(wen)下(xia)硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)強度僅(jin)是(shi)(shi)天然(ran)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)或(huo)某些合(he)成橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)一半,但在200℃以上的(de)(de)(de)高(gao)(gao)溫(wen)(wen)(wen)(wen)(wen)(wen)環(huan)境(jing)下(xia),硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)(neng)(neng)(neng)(neng)保持一定(ding)的(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)和表面硬度,且力學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)無明顯(xian)變(bian)化。(2)低(di)溫(wen)(wen)(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)玻璃化溫(wen)(wen)(wen)(wen)(wen)(wen)度一般為-70~-50℃,特(te)殊配方可達-100℃,表明其低(di)溫(wen)(wen)(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)優異(yi)(yi)。這對(dui)(dui)(dui)航(hang)空、宇航(hang)工(gong)業(ye)的(de)(de)(de)意義重大。(3)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵對(dui)(dui)(dui)氧(yang)、臭氧(yang)及紫外線等(deng)十分穩(wen)定(ding),在不加(jia)任何添(tian)加(jia)劑(ji)的(de)(de)(de)情(qing)況(kuang)下(xia),就具有(you)優良的(de)(de)(de)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)。硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)具有(you)優異(yi)(yi)的(de)(de)(de)絕緣(yuan)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng),耐(nai)電暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)電弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非常(chang)好。(5)物(wu)(wu)理機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)。硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)常(chang)溫(wen)(wen)(wen)(wen)(wen)(wen)下(xia)的(de)(de)(de)物(wu)(wu)理機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)比(bi)通用橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)差,但在150℃的(de)(de)(de)高(gao)(gao)溫(wen)(wen)(wen)(wen)(wen)(wen)和-50℃的(de)(de)(de)低(di)溫(wen)(wen)(wen)(wen)(wen)(wen)下(xia),其物(wu)(wu)理機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)優于通用橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)油及化學試劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)具有(you)中等(deng)的(de)(de)(de)耐(nai)油、耐(nai)溶劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)。(7)氣(qi)(qi)體(ti)透(tou)過(guo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)(neng)。室(shi)溫(wen)(wen)(wen)(wen)(wen)(wen)下(xia)硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)對(dui)(dui)(dui)空氣(qi)(qi)、氮、氧(yang)、二(er)氧(yang)化碳等(deng)氣(qi)(qi)體(ti)的(de)(de)(de)透(tou)氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比(bi)天然(ran)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)高(gao)(gao)出30-50倍(bei)。(8)生理惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)無毒,無味,無嗅,與人體(ti)組織不粘連(lian),具有(you)抗凝血作用,對(dui)(dui)(dui)肌體(ti)組織的(de)(de)(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常(chang)少。特(te)別適合(he)作為醫用材(cai)料(liao)。
硅橡膠的用量
據中國(guo)(guo)汽(qi)車(che)(che)工(gong)業協會統計,2012年(nian)(nian),汽(qi)車(che)(che)產(chan)(chan)銷分別(bie)達(da)到1927.18萬輛(liang)和(he)1930.64萬輛(liang),同比分別(bie)增(zeng)(zeng)長4.63%和(he)4.33%,汽(qi)車(che)(che)工(gong)業硅橡(xiang)膠的用(yong)量(liang)約(yue)達(da)2.0萬t。根據觀研天下的新研究,增(zeng)(zeng)加有(you)機(ji)硅材料在汽(qi)車(che)(che)零部(bu)件(jian)方面(mian)的用(yong)量(liang),可以(yi)(yi)大幅度提(ti)(ti)高汽(qi)車(che)(che)的安全性能,因此(ci),汽(qi)車(che)(che)產(chan)(chan)量(liang)和(he)單車(che)(che)用(yong)量(liang)水平的提(ti)(ti)高都將推動(dong)汽(qi)車(che)(che)工(gong)業對硅橡(xiang)膠需求的增(zeng)(zeng)加。國(guo)(guo)家鼓(gu)勵自(zi)(zi)主(zhu)品牌(pai)的汽(qi)車(che)(che)發展,關(guan)鍵汽(qi)車(che)(che)零部(bu)件(jian)實現自(zi)(zi)主(zhu)化,《2012年(nian)(nian)度黨政(zheng)機(ji)關(guan)公務(wu)用(yong)車(che)(che)選用(yong)車(che)(che)型(xing)目錄(征(zheng)求意見稿)》為自(zi)(zi)主(zhu)品牌(pai)擴大在政(zheng)府采購的市場份額(e),為改變目前(qian)國(guo)(guo)內政(zheng)府采購以(yi)(yi)合資品牌(pai)產(chan)(chan)品為主(zhu)的局(ju)面(mian)提(ti)(ti)供了保(bao)障(zhang)。促(cu)進(jin)自(zi)(zi)主(zhu)品牌(pai)發展,國(guo)(guo)產(chan)(chan)汽(qi)車(che)(che)業的繁榮將為汽(qi)車(che)(che)膠的應用(yong)提(ti)(ti)供有(you)力保(bao)障(zhang)。預(yu)測未(wei)來3年(nian)(nian),我國(guo)(guo)室溫(wen)硫(liu)化硅橡(xiang)膠在汽(qi)車(che)(che)行業將以(yi)(yi)年(nian)(nian)均20%增(zeng)(zeng)長。
此外(wai),硅(gui)(gui)(gui)橡(xiang)膠(jiao)是重要的(de)(de)非(fei)石(shi)油基合(he)成(cheng)(cheng)橡(xiang)膠(jiao),約(yue)占非(fei)石(shi)油基合(he)成(cheng)(cheng)橡(xiang)膠(jiao)消(xiao)費(fei)量的(de)(de)98%。但因為(wei)石(shi)油價格的(de)(de)大(da)幅上漲,同(tong)時(shi)我(wo)國(guo)(guo)在(zai)硅(gui)(gui)(gui)橡(xiang)膠(jiao)的(de)(de)關鍵原料有(you)機(ji)硅(gui)(gui)(gui)單體的(de)(de)生產(chan)(chan)(chan)(chan)技術方面(mian)取得突破,有(you)機(ji)硅(gui)(gui)(gui)單體的(de)(de)生產(chan)(chan)(chan)(chan)技術在(zai)2005年(nian)(nian)前(qian)被幾家跨國(guo)(guo)公司(si)壟斷,但目前(qian)我(wo)國(guo)(guo)已(yi)發展成(cheng)(cheng)為(wei)全球(qiu)有(you)機(ji)硅(gui)(gui)(gui)單體第1大(da)國(guo)(guo),這2個方面(mian)原因使硅(gui)(gui)(gui)橡(xiang)膠(jiao)的(de)(de)價格從2011年(nian)(nian)起開(kai)始低(di)于(yu)石(shi)油基合(he)成(cheng)(cheng)橡(xiang)膠(jiao),僅(jin)約(yue)為(wei)大(da)宗石(shi)油基橡(xiang)膠(jiao)的(de)(de)80%~90%,成(cheng)(cheng)為(wei)廉價的(de)(de)合(he)成(cheng)(cheng)橡(xiang)膠(jiao),并(bing)開(kai)始大(da)規模替代(dai)石(shi)油基合(he)成(cheng)(cheng)橡(xiang)膠(jiao)。這將極大(da)拓展有(you)機(ji)硅(gui)(gui)(gui)產(chan)(chan)(chan)(chan)業的(de)(de)市場空間,同(tong)時(shi)將帶動硅(gui)(gui)(gui)油、硅(gui)(gui)(gui)烷偶聯劑(ji)和硅(gui)(gui)(gui)樹脂等其他有(you)機(ji)硅(gui)(gui)(gui)產(chan)(chan)(chan)(chan)品的(de)(de)消(xiao)費(fei)。