
硅橡膠是指主(zhu)鏈(lian)由(you)硅(gui)(gui)(gui)和氧(yang)(yang)原子交替構成(cheng),硅(gui)(gui)(gui)原子上(shang)(shang)通常連有兩(liang)個有機基(ji)團的(de)橡膠(jiao)。普通的(de)硅(gui)(gui)(gui)橡膠(jiao)主(zhu)要由(you)含(han)甲基(ji)和少量(liang)乙烯基(ji)的(de)硅(gui)(gui)(gui)氧(yang)(yang)鏈(lian)節組成(cheng)。苯基(ji)的(de)引(yin)入可(ke)(ke)提高(gao)(gao)硅(gui)(gui)(gui)橡膠(jiao)的(de)耐(nai)高(gao)(gao)、低(di)溫(wen)性(xing)(xing)能,三氟丙基(ji)及氰(qing)基(ji)的(de)引(yin)入則可(ke)(ke)提高(gao)(gao)硅(gui)(gui)(gui)橡膠(jiao)的(de)耐(nai)溫(wen)及耐(nai)油性(xing)(xing)能。硅(gui)(gui)(gui)橡膠(jiao)耐(nai)低(di)溫(wen)性(xing)(xing)能良(liang)好,一般在-55℃下仍能工作(zuo)。引(yin)入苯基(ji)后,可(ke)(ke)達-73℃。硅(gui)(gui)(gui)橡膠(jiao)的(de)耐(nai)熱性(xing)(xing)能也很(hen)突出,在180℃下可(ke)(ke)長期(qi)工作(zuo),稍高(gao)(gao)于(yu)200℃也能承受(shou)數(shu)周或更長時(shi)間仍有彈性(xing)(xing),瞬時(shi)可(ke)(ke)耐(nai)300℃以上(shang)(shang)的(de)高(gao)(gao)溫(wen)。硅(gui)(gui)(gui)橡膠(jiao)的(de)透氣(qi)性(xing)(xing)好,氧(yang)(yang)氣(qi)透過率在合(he)成(cheng)聚合(he)物中是較高(gao)(gao)的(de)。此外,硅(gui)(gui)(gui)橡膠(jiao)還具有生理惰(duo)性(xing)(xing)、不(bu)會(hui)導致凝血的(de)突出特性(xing)(xing),因此在醫用領域應用廣泛。
主要品種
硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)分(fen)(fen)類的方法(fa)很多,通常(chang)按固(gu)化前的形態分(fen)(fen)為固(gu)體硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)和液體硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao);按硫化溫(wen)度分(fen)(fen)為室溫(wen)硫化硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao),高溫(wen)硫化硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao);按所用(yong)單(dan)體的不(bu)同(tong),可分(fen)(fen)為甲(jia)基乙烯基硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao),甲(jia)基苯基乙烯基硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)、氟硅(gui)(gui)(gui)(gui),腈硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)等;按性能和用(yong)途的不(bu)同(tong)又可分(fen)(fen)為通用(yong)型(xing)、超(chao)耐(nai)低(di)溫(wen)型(xing)、超(chao)耐(nai)高溫(wen)型(xing)、高強力型(xing)、耐(nai)油型(xing)、醫用(yong)型(xing)等等。
發展史
硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)早期是由(you)美國(guo)(guo)以三氯化(hua)(hua)鐵為催化(hua)(hua)劑合(he)(he)成(cheng)的(de)。1945年,硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)產品(pin)問(wen)世。1948年,采用高比表面積的(de)氣(qi)相法白炭黑(hei)補強的(de)硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)研制(zhi)成(cheng)功,使硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)性能躍升到實用階段,奠(dian)定了現代(dai)硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)生(sheng)(sheng)產技術的(de)基礎。從(cong)二甲(jia)基二氯硅(gui)(gui)(gui)烷(wan)合(he)(he)成(cheng)開(kai)始(shi)生(sheng)(sheng)產硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)國(guo)(guo)家有(you)美國(guo)(guo)。俄(e)羅(luo)斯(si)、德國(guo)(guo)、日(ri)本、韓國(guo)(guo)和(he)中(zhong)國(guo)(guo)等。中(zhong)國(guo)(guo)硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)工業化(hua)(hua)研究始(shi)于1957年,多家研究所和(he)企業陸續開(kai)發出各種硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)。到2003年底,中(zhong)國(guo)(guo)硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)生(sheng)(sheng)產能力(li)為135千(qian)噸,其中(zhong)高溫膠(jiao)(jiao)100千(qian)噸。
高溫硫化硅橡膠
高(gao)溫(wen)硫(liu)化硅(gui)橡(xiang)膠(jiao)(jiao)是(shi)指聚硅(gui)氧(yang)烷變成(cheng)彈性體(ti)的(de)(de)(de)過(guo)程是(shi)經過(guo)高(gao)溫(wen)(110-170℃)硫(liu)化成(cheng)型的(de)(de)(de)。它主(zhu)要以高(gao)分子量(liang)的(de)(de)(de)聚甲基乙烯基硅(gui)氧(yang)烷為生膠(jiao)(jiao),混入補強(qiang)(qiang)(qiang)填料(liao)、硫(liu)化劑等(deng),在加(jia)熱加(jia)壓(ya)下硫(liu)化成(cheng)彈性體(ti)。硅(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)(de)補強(qiang)(qiang)(qiang)主(zhu)要是(shi)各種類型的(de)(de)(de)白炭(tan)黑,可使(shi)硫(liu)化膠(jiao)(jiao)的(de)(de)(de)強(qiang)(qiang)(qiang)度增(zeng)加(jia)數十倍。有(you)時為了降低(di)成(cheng)本或改善膠(jiao)(jiao)料(liao)性能及賦予硫(liu)化膠(jiao)(jiao)各種特殊的(de)(de)(de)性能,也(ye)加(jia)入相應的(de)(de)(de)各種添加(jia)劑。硫(liu)化劑是(shi)各種有(you)機過(guo)氧(yang)化物(wu)或加(jia)成(cheng)反應催(cui)化劑。
加工成型方法如圖(tu)所示。一次硫(liu)化(hua)的(de)目的(de)是進(jin)(jin)行高分(fen)子鏈的(de)交聯反應;二次硫(liu)化(hua)的(de)目的(de)是進(jin)(jin)行補充交聯、驅除(chu)硫(liu)化(hua)劑(ji)分(fen)解產物和其他(ta)揮發性化(hua)合物以穩定硫(liu)化(hua)膠(jiao)的(de)各(ge)項性能。常用的(de)設備有開放式(shi)煉膠(jiao)機、捏合機及(ji)真空密(mi)煉機。
主要性能
(1)高溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)顯著的(de)(de)特征是高溫(wen)(wen)(wen)(wen)穩(wen)定性(xing)(xing)(xing)(xing)(xing)(xing),雖然(ran)常溫(wen)(wen)(wen)(wen)下(xia)(xia)(xia)硅橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)強度(du)僅是天(tian)然(ran)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)或(huo)某些合(he)(he)成橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)一半,但在200℃以上的(de)(de)高溫(wen)(wen)(wen)(wen)環境下(xia)(xia)(xia),硅橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)(neng)保持一定的(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)和(he)表面(mian)硬度(du),且力學性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)無(wu)明(ming)顯變化(hua)。(2)低(di)溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)硅橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)玻璃化(hua)溫(wen)(wen)(wen)(wen)度(du)一般(ban)為-70~-50℃,特殊配方可達-100℃,表明(ming)其低(di)溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優(you)異(yi)。這(zhe)對航空、宇航工(gong)業的(de)(de)意義重大。(3)耐(nai)候(hou)(hou)性(xing)(xing)(xing)(xing)(xing)(xing)硅橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵對氧(yang)、臭(chou)氧(yang)及(ji)紫外線等(deng)十分穩(wen)定,在不加(jia)任何添加(jia)劑(ji)的(de)(de)情況下(xia)(xia)(xia),就具(ju)有(you)(you)優(you)良的(de)(de)耐(nai)候(hou)(hou)性(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)具(ju)有(you)(you)優(you)異(yi)的(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng),耐(nai)電(dian)暈(yun)性(xing)(xing)(xing)(xing)(xing)(xing)和(he)耐(nai)電(dian)弧(hu)性(xing)(xing)(xing)(xing)(xing)(xing)也非(fei)常好。(5)物理機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)常溫(wen)(wen)(wen)(wen)下(xia)(xia)(xia)的(de)(de)物理機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)比通(tong)用(yong)(yong)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)差,但在150℃的(de)(de)高溫(wen)(wen)(wen)(wen)和(he)-50℃的(de)(de)低(di)溫(wen)(wen)(wen)(wen)下(xia)(xia)(xia),其物理機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優(you)于通(tong)用(yong)(yong)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)油及(ji)化(hua)學試劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)硅橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)具(ju)有(you)(you)中等(deng)的(de)(de)耐(nai)油、耐(nai)溶劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。(7)氣(qi)體(ti)透(tou)過性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。室(shi)溫(wen)(wen)(wen)(wen)下(xia)(xia)(xia)硅橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)對空氣(qi)、氮(dan)、氧(yang)、二氧(yang)化(hua)碳等(deng)氣(qi)體(ti)的(de)(de)透(tou)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)比天(tian)然(ran)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)高出30-50倍。(8)生理惰性(xing)(xing)(xing)(xing)(xing)(xing)。硅橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)無(wu)毒,無(wu)味,無(wu)嗅(xiu),與人(ren)體(ti)組織(zhi)不粘(zhan)連,具(ju)有(you)(you)抗凝血作用(yong)(yong),對肌體(ti)組織(zhi)的(de)(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)非(fei)常少。特別適合(he)(he)作為醫用(yong)(yong)材料(liao)。
硅橡膠的用量
據(ju)中國(guo)汽車(che)工(gong)(gong)業協會統(tong)計,2012年,汽車(che)產(chan)銷(xiao)分別(bie)達到1927.18萬(wan)輛和1930.64萬(wan)輛,同比分別(bie)增長4.63%和4.33%,汽車(che)工(gong)(gong)業硅(gui)(gui)橡膠的(de)用(yong)量(liang)約達2.0萬(wan)t。根據(ju)觀研天下的(de)新研究(jiu),增加有機(ji)硅(gui)(gui)材料在(zai)汽車(che)零部件方面的(de)用(yong)量(liang),可以大(da)幅度提(ti)(ti)高汽車(che)的(de)安全(quan)性(xing)能,因此(ci),汽車(che)產(chan)量(liang)和單車(che)用(yong)量(liang)水平的(de)提(ti)(ti)高都將推(tui)動(dong)汽車(che)工(gong)(gong)業對(dui)硅(gui)(gui)橡膠需求的(de)增加。國(guo)家(jia)鼓(gu)勵自主(zhu)(zhu)品(pin)牌的(de)汽車(che)發(fa)展,關鍵(jian)汽車(che)零部件實現自主(zhu)(zhu)化,《2012年度黨(dang)政機(ji)關公務用(yong)車(che)選用(yong)車(che)型目(mu)(mu)錄(征求意見(jian)稿)》為(wei)自主(zhu)(zhu)品(pin)牌擴大(da)在(zai)政府采購的(de)市場(chang)份額,為(wei)改變(bian)目(mu)(mu)前國(guo)內(nei)政府采購以合資(zi)品(pin)牌產(chan)品(pin)為(wei)主(zhu)(zhu)的(de)局面提(ti)(ti)供(gong)了保障。促(cu)進(jin)自主(zhu)(zhu)品(pin)牌發(fa)展,國(guo)產(chan)汽車(che)業的(de)繁榮將為(wei)汽車(che)膠的(de)應用(yong)提(ti)(ti)供(gong)有力(li)保障。預測未來(lai)3年,我國(guo)室溫硫化硅(gui)(gui)橡膠在(zai)汽車(che)行(xing)業將以年均20%增長。
此外,硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)是重要的(de)非石(shi)(shi)(shi)(shi)油(you)(you)(you)基(ji)合(he)成(cheng)橡(xiang)(xiang)膠(jiao),約(yue)占(zhan)非石(shi)(shi)(shi)(shi)油(you)(you)(you)基(ji)合(he)成(cheng)橡(xiang)(xiang)膠(jiao)消(xiao)費量(liang)的(de)98%。但(dan)因為(wei)(wei)石(shi)(shi)(shi)(shi)油(you)(you)(you)價格(ge)的(de)大(da)幅上漲,同(tong)時(shi)我國(guo)在(zai)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)關鍵原(yuan)料有(you)機(ji)硅(gui)(gui)(gui)(gui)單(dan)體的(de)生(sheng)產技(ji)術方面(mian)取得(de)突破,有(you)機(ji)硅(gui)(gui)(gui)(gui)單(dan)體的(de)生(sheng)產技(ji)術在(zai)2005年前被幾(ji)家(jia)跨國(guo)公司壟斷(duan),但(dan)目(mu)前我國(guo)已發(fa)展(zhan)成(cheng)為(wei)(wei)全球有(you)機(ji)硅(gui)(gui)(gui)(gui)單(dan)體第1大(da)國(guo),這2個(ge)方面(mian)原(yuan)因使硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)價格(ge)從2011年起開(kai)(kai)始低于石(shi)(shi)(shi)(shi)油(you)(you)(you)基(ji)合(he)成(cheng)橡(xiang)(xiang)膠(jiao),僅約(yue)為(wei)(wei)大(da)宗石(shi)(shi)(shi)(shi)油(you)(you)(you)基(ji)橡(xiang)(xiang)膠(jiao)的(de)80%~90%,成(cheng)為(wei)(wei)廉價的(de)合(he)成(cheng)橡(xiang)(xiang)膠(jiao),并開(kai)(kai)始大(da)規(gui)模替代石(shi)(shi)(shi)(shi)油(you)(you)(you)基(ji)合(he)成(cheng)橡(xiang)(xiang)膠(jiao)。這將(jiang)極大(da)拓展(zhan)有(you)機(ji)硅(gui)(gui)(gui)(gui)產業(ye)的(de)市(shi)場空(kong)間,同(tong)時(shi)將(jiang)帶動硅(gui)(gui)(gui)(gui)油(you)(you)(you)、硅(gui)(gui)(gui)(gui)烷偶聯劑和硅(gui)(gui)(gui)(gui)樹脂等(deng)其他有(you)機(ji)硅(gui)(gui)(gui)(gui)產品的(de)消(xiao)費。