硅橡膠是(shi)指(zhi)主鏈(lian)由硅(gui)(gui)(gui)(gui)和(he)氧(yang)原子(zi)交替構成,硅(gui)(gui)(gui)(gui)原子(zi)上(shang)通(tong)常連有(you)兩個有(you)機基(ji)團的(de)(de)(de)橡(xiang)(xiang)膠(jiao)。普通(tong)的(de)(de)(de)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)主要由含甲基(ji)和(he)少量乙烯基(ji)的(de)(de)(de)硅(gui)(gui)(gui)(gui)氧(yang)鏈(lian)節組成。苯(ben)基(ji)的(de)(de)(de)引(yin)入(ru)(ru)可(ke)提(ti)高(gao)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)耐高(gao)、低溫性(xing)(xing)(xing)能(neng),三(san)氟丙基(ji)及氰(qing)基(ji)的(de)(de)(de)引(yin)入(ru)(ru)則(ze)可(ke)提(ti)高(gao)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)耐溫及耐油性(xing)(xing)(xing)能(neng)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)耐低溫性(xing)(xing)(xing)能(neng)良好,一般在(zai)-55℃下(xia)仍能(neng)工(gong)作(zuo)。引(yin)入(ru)(ru)苯(ben)基(ji)后(hou),可(ke)達-73℃。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)耐熱性(xing)(xing)(xing)能(neng)也很突出(chu),在(zai)180℃下(xia)可(ke)長期工(gong)作(zuo),稍高(gao)于200℃也能(neng)承(cheng)受數(shu)周或更(geng)長時間仍有(you)彈性(xing)(xing)(xing),瞬時可(ke)耐300℃以上(shang)的(de)(de)(de)高(gao)溫。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)透(tou)氣性(xing)(xing)(xing)好,氧(yang)氣透(tou)過率在(zai)合(he)成聚合(he)物中(zhong)是(shi)較高(gao)的(de)(de)(de)。此外,硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)還具有(you)生理惰性(xing)(xing)(xing)、不(bu)會導(dao)致凝血的(de)(de)(de)突出(chu)特性(xing)(xing)(xing),因此在(zai)醫用(yong)領(ling)域應用(yong)廣泛(fan)。
主要品種
硅橡(xiang)膠(jiao)分(fen)(fen)類的方法很多,通(tong)(tong)常按固化(hua)前的形態(tai)分(fen)(fen)為固體(ti)硅橡(xiang)膠(jiao)和液體(ti)硅橡(xiang)膠(jiao);按硫(liu)化(hua)溫度分(fen)(fen)為室溫硫(liu)化(hua)硅橡(xiang)膠(jiao),高(gao)(gao)溫硫(liu)化(hua)硅橡(xiang)膠(jiao);按所用單體(ti)的不同(tong),可(ke)(ke)分(fen)(fen)為甲基乙烯基硅橡(xiang)膠(jiao),甲基苯基乙烯基硅橡(xiang)膠(jiao)、氟硅,腈硅橡(xiang)膠(jiao)等;按性能(neng)和用途(tu)的不同(tong)又可(ke)(ke)分(fen)(fen)為通(tong)(tong)用型、超耐(nai)低溫型、超耐(nai)高(gao)(gao)溫型、高(gao)(gao)強(qiang)力(li)型、耐(nai)油型、醫(yi)用型等等。
發展史
硅(gui)(gui)(gui)橡膠(jiao)(jiao)早(zao)期是由美國以三氯(lv)化(hua)(hua)鐵為(wei)(wei)催化(hua)(hua)劑合(he)(he)成的(de)(de)。1945年(nian)(nian),硅(gui)(gui)(gui)橡膠(jiao)(jiao)產(chan)(chan)品問世。1948年(nian)(nian),采用高(gao)比表面(mian)積(ji)的(de)(de)氣(qi)相法白炭黑(hei)補強的(de)(de)硅(gui)(gui)(gui)橡膠(jiao)(jiao)研(yan)制成功,使硅(gui)(gui)(gui)橡膠(jiao)(jiao)的(de)(de)性能躍(yue)升到實用階段,奠(dian)定了現代(dai)硅(gui)(gui)(gui)橡膠(jiao)(jiao)生(sheng)產(chan)(chan)技術(shu)的(de)(de)基礎。從二(er)甲基二(er)氯(lv)硅(gui)(gui)(gui)烷合(he)(he)成開始生(sheng)產(chan)(chan)硅(gui)(gui)(gui)橡膠(jiao)(jiao)的(de)(de)國家有(you)美國。俄羅斯、德國、日(ri)本、韓國和中(zhong)(zhong)國等(deng)。中(zhong)(zhong)國硅(gui)(gui)(gui)橡膠(jiao)(jiao)的(de)(de)工(gong)業(ye)化(hua)(hua)研(yan)究始于1957年(nian)(nian),多家研(yan)究所和企業(ye)陸續開發出(chu)各種硅(gui)(gui)(gui)橡膠(jiao)(jiao)。到2003年(nian)(nian)底,中(zhong)(zhong)國硅(gui)(gui)(gui)橡膠(jiao)(jiao)生(sheng)產(chan)(chan)能力為(wei)(wei)135千噸(dun),其(qi)中(zhong)(zhong)高(gao)溫膠(jiao)(jiao)100千噸(dun)。
高溫硫化硅橡膠
高(gao)溫硫(liu)化(hua)(hua)(hua)硅(gui)(gui)(gui)橡(xiang)膠是(shi)指聚硅(gui)(gui)(gui)氧(yang)烷(wan)變成(cheng)(cheng)彈性體(ti)的(de)過(guo)程是(shi)經過(guo)高(gao)溫(110-170℃)硫(liu)化(hua)(hua)(hua)成(cheng)(cheng)型(xing)的(de)。它主要以高(gao)分子量的(de)聚甲(jia)基(ji)乙烯基(ji)硅(gui)(gui)(gui)氧(yang)烷(wan)為(wei)生膠,混(hun)入補(bu)強(qiang)填(tian)料(liao)(liao)、硫(liu)化(hua)(hua)(hua)劑(ji)(ji)等,在加熱加壓下硫(liu)化(hua)(hua)(hua)成(cheng)(cheng)彈性體(ti)。硅(gui)(gui)(gui)橡(xiang)膠的(de)補(bu)強(qiang)主要是(shi)各(ge)(ge)種(zhong)(zhong)(zhong)類型(xing)的(de)白炭黑,可使硫(liu)化(hua)(hua)(hua)膠的(de)強(qiang)度增加數十倍。有時為(wei)了降低成(cheng)(cheng)本或改善膠料(liao)(liao)性能(neng)及(ji)賦予硫(liu)化(hua)(hua)(hua)膠各(ge)(ge)種(zhong)(zhong)(zhong)特(te)殊的(de)性能(neng),也加入相應的(de)各(ge)(ge)種(zhong)(zhong)(zhong)添(tian)加劑(ji)(ji)。硫(liu)化(hua)(hua)(hua)劑(ji)(ji)是(shi)各(ge)(ge)種(zhong)(zhong)(zhong)有機過(guo)氧(yang)化(hua)(hua)(hua)物(wu)或加成(cheng)(cheng)反應催化(hua)(hua)(hua)劑(ji)(ji)。
加工(gong)成型(xing)方(fang)法如圖所(suo)示(shi)。一(yi)次(ci)硫化(hua)(hua)(hua)的(de)(de)(de)目的(de)(de)(de)是進行(xing)高分(fen)子鏈(lian)的(de)(de)(de)交聯反應;二(er)次(ci)硫化(hua)(hua)(hua)的(de)(de)(de)目的(de)(de)(de)是進行(xing)補充交聯、驅除硫化(hua)(hua)(hua)劑分(fen)解產(chan)物和其他揮發性化(hua)(hua)(hua)合物以穩定硫化(hua)(hua)(hua)膠的(de)(de)(de)各(ge)項性能。常(chang)用的(de)(de)(de)設(she)備有開放(fang)式煉膠機、捏合機及真空(kong)密煉機。
主要性能
(1)高溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)顯著(zhu)的(de)(de)特征是高溫(wen)(wen)(wen)穩(wen)定(ding)(ding)性(xing)(xing)(xing)(xing)(xing),雖然(ran)常溫(wen)(wen)(wen)下硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)強度(du)僅是天(tian)然(ran)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)或(huo)某些合(he)成(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)一(yi)半,但(dan)在200℃以上的(de)(de)高溫(wen)(wen)(wen)環境下,硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)仍(reng)能(neng)(neng)保持一(yi)定(ding)(ding)的(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)、回(hui)彈性(xing)(xing)(xing)(xing)(xing)和表面硬(ying)度(du),且力學(xue)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)無(wu)(wu)明顯變(bian)化。(2)低(di)(di)溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)玻(bo)璃化溫(wen)(wen)(wen)度(du)一(yi)般為-70~-50℃,特殊配方(fang)可(ke)達-100℃,表明其(qi)(qi)低(di)(di)溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)(you)異。這對(dui)(dui)航空、宇航工業(ye)的(de)(de)意義重大。(3)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵對(dui)(dui)氧、臭氧及紫外線等十分穩(wen)定(ding)(ding),在不加任何添(tian)加劑的(de)(de)情況下,就具(ju)(ju)有(you)(you)(you)優(you)(you)良的(de)(de)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)(ju)有(you)(you)(you)優(you)(you)異的(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)能(neng)(neng),耐(nai)(nai)電(dian)暈性(xing)(xing)(xing)(xing)(xing)和耐(nai)(nai)電(dian)弧(hu)性(xing)(xing)(xing)(xing)(xing)也非(fei)常好。(5)物(wu)理(li)機械性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)常溫(wen)(wen)(wen)下的(de)(de)物(wu)理(li)機械性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)比(bi)通(tong)(tong)用橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)差(cha),但(dan)在150℃的(de)(de)高溫(wen)(wen)(wen)和-50℃的(de)(de)低(di)(di)溫(wen)(wen)(wen)下,其(qi)(qi)物(wu)理(li)機械性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)(you)于通(tong)(tong)用橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)(nai)油及化學(xue)試劑性(xing)(xing)(xing)(xing)(xing)。普通(tong)(tong)硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)(ju)有(you)(you)(you)中等的(de)(de)耐(nai)(nai)油、耐(nai)(nai)溶劑性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。(7)氣(qi)體(ti)透過(guo)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。室(shi)溫(wen)(wen)(wen)下硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)對(dui)(dui)空氣(qi)、氮(dan)、氧、二氧化碳等氣(qi)體(ti)的(de)(de)透氣(qi)性(xing)(xing)(xing)(xing)(xing)比(bi)天(tian)然(ran)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)高出30-50倍。(8)生(sheng)理(li)惰性(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)無(wu)(wu)毒,無(wu)(wu)味,無(wu)(wu)嗅(xiu),與人(ren)體(ti)組織(zhi)不粘連,具(ju)(ju)有(you)(you)(you)抗(kang)凝血作(zuo)用,對(dui)(dui)肌體(ti)組織(zhi)的(de)(de)反應性(xing)(xing)(xing)(xing)(xing)非(fei)常少。特別適合(he)作(zuo)為醫用材料。
硅橡膠的用量
據(ju)中(zhong)國汽(qi)(qi)(qi)車(che)(che)工(gong)業協會統計(ji),2012年,汽(qi)(qi)(qi)車(che)(che)產銷分別(bie)達到1927.18萬(wan)輛和1930.64萬(wan)輛,同比分別(bie)增(zeng)長4.63%和4.33%,汽(qi)(qi)(qi)車(che)(che)工(gong)業硅(gui)橡膠(jiao)的用(yong)(yong)量(liang)約達2.0萬(wan)t。根據(ju)觀研(yan)天下的新(xin)研(yan)究,增(zeng)加有(you)機硅(gui)材料在汽(qi)(qi)(qi)車(che)(che)零部(bu)件方面的用(yong)(yong)量(liang),可以(yi)大幅度提(ti)(ti)高汽(qi)(qi)(qi)車(che)(che)的安全(quan)性(xing)能,因此,汽(qi)(qi)(qi)車(che)(che)產量(liang)和單(dan)車(che)(che)用(yong)(yong)量(liang)水平的提(ti)(ti)高都(dou)將(jiang)推動汽(qi)(qi)(qi)車(che)(che)工(gong)業對硅(gui)橡膠(jiao)需(xu)求(qiu)的增(zeng)加。國家鼓(gu)勵自(zi)主品牌(pai)的汽(qi)(qi)(qi)車(che)(che)發展(zhan),關(guan)鍵汽(qi)(qi)(qi)車(che)(che)零部(bu)件實現自(zi)主化(hua),《2012年度黨政機關(guan)公務用(yong)(yong)車(che)(che)選用(yong)(yong)車(che)(che)型目錄(征(zheng)求(qiu)意見(jian)稿)》為(wei)(wei)自(zi)主品牌(pai)擴大在政府(fu)(fu)采購的市(shi)場(chang)份額,為(wei)(wei)改(gai)變目前國內政府(fu)(fu)采購以(yi)合資(zi)品牌(pai)產品為(wei)(wei)主的局面提(ti)(ti)供了(le)保障。促進自(zi)主品牌(pai)發展(zhan),國產汽(qi)(qi)(qi)車(che)(che)業的繁榮(rong)將(jiang)為(wei)(wei)汽(qi)(qi)(qi)車(che)(che)膠(jiao)的應用(yong)(yong)提(ti)(ti)供有(you)力保障。預(yu)測未來3年,我(wo)國室溫硫化(hua)硅(gui)橡膠(jiao)在汽(qi)(qi)(qi)車(che)(che)行(xing)業將(jiang)以(yi)年均20%增(zeng)長。
此外,硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)是重要的(de)(de)(de)非石(shi)(shi)(shi)油(you)(you)基合成(cheng)橡(xiang)(xiang)膠(jiao)(jiao),約占非石(shi)(shi)(shi)油(you)(you)基合成(cheng)橡(xiang)(xiang)膠(jiao)(jiao)消費量的(de)(de)(de)98%。但(dan)因為(wei)石(shi)(shi)(shi)油(you)(you)價(jia)格的(de)(de)(de)大幅(fu)上(shang)漲,同(tong)時我(wo)國在硅(gui)(gui)(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)(gui)(gui)單(dan)(dan)體的(de)(de)(de)生(sheng)產技(ji)術方面(mian)(mian)取得突破,有(you)(you)機(ji)硅(gui)(gui)(gui)(gui)單(dan)(dan)體的(de)(de)(de)生(sheng)產技(ji)術在2005年(nian)前被幾(ji)家跨國公司壟斷,但(dan)目前我(wo)國已發展成(cheng)為(wei)全球有(you)(you)機(ji)硅(gui)(gui)(gui)(gui)單(dan)(dan)體第1大國,這(zhe)2個方面(mian)(mian)原(yuan)因使硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)價(jia)格從2011年(nian)起開(kai)始(shi)低于石(shi)(shi)(shi)油(you)(you)基合成(cheng)橡(xiang)(xiang)膠(jiao)(jiao),僅約為(wei)大宗石(shi)(shi)(shi)油(you)(you)基橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)80%~90%,成(cheng)為(wei)廉價(jia)的(de)(de)(de)合成(cheng)橡(xiang)(xiang)膠(jiao)(jiao),并開(kai)始(shi)大規(gui)模替(ti)代石(shi)(shi)(shi)油(you)(you)基合成(cheng)橡(xiang)(xiang)膠(jiao)(jiao)。這(zhe)將極大拓展有(you)(you)機(ji)硅(gui)(gui)(gui)(gui)產業的(de)(de)(de)市場空(kong)間(jian),同(tong)時將帶動硅(gui)(gui)(gui)(gui)油(you)(you)、硅(gui)(gui)(gui)(gui)烷偶聯劑和硅(gui)(gui)(gui)(gui)樹脂等其他有(you)(you)機(ji)硅(gui)(gui)(gui)(gui)產品的(de)(de)(de)消費。