
硅橡膠是(shi)指(zhi)主(zhu)鏈由(you)硅(gui)(gui)和氧原(yuan)子(zi)交替(ti)構成,硅(gui)(gui)原(yuan)子(zi)上(shang)通常連有(you)(you)兩個有(you)(you)機(ji)基(ji)團的(de)(de)(de)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)。普(pu)通的(de)(de)(de)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)主(zhu)要由(you)含甲基(ji)和少量乙烯基(ji)的(de)(de)(de)硅(gui)(gui)氧鏈節組成。苯(ben)基(ji)的(de)(de)(de)引(yin)入可提(ti)高(gao)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)耐(nai)(nai)(nai)高(gao)、低(di)溫性(xing)(xing)(xing)能(neng),三氟(fu)丙基(ji)及氰基(ji)的(de)(de)(de)引(yin)入則可提(ti)高(gao)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)耐(nai)(nai)(nai)溫及耐(nai)(nai)(nai)油(you)性(xing)(xing)(xing)能(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)耐(nai)(nai)(nai)低(di)溫性(xing)(xing)(xing)能(neng)良(liang)好,一般在(zai)(zai)-55℃下(xia)仍(reng)能(neng)工(gong)作(zuo)。引(yin)入苯(ben)基(ji)后,可達-73℃。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)耐(nai)(nai)(nai)熱性(xing)(xing)(xing)能(neng)也(ye)很(hen)突(tu)出(chu),在(zai)(zai)180℃下(xia)可長(chang)期工(gong)作(zuo),稍高(gao)于200℃也(ye)能(neng)承受數周或更長(chang)時間仍(reng)有(you)(you)彈性(xing)(xing)(xing),瞬時可耐(nai)(nai)(nai)300℃以上(shang)的(de)(de)(de)高(gao)溫。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)透(tou)氣(qi)(qi)性(xing)(xing)(xing)好,氧氣(qi)(qi)透(tou)過率在(zai)(zai)合(he)成聚合(he)物中是(shi)較高(gao)的(de)(de)(de)。此外,硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)還具有(you)(you)生理(li)惰(duo)性(xing)(xing)(xing)、不會(hui)導致凝血(xue)的(de)(de)(de)突(tu)出(chu)特(te)性(xing)(xing)(xing),因此在(zai)(zai)醫用領域應用廣(guang)泛。
主(zhu)要品(pin)種(zhong)
硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)分(fen)(fen)(fen)類的方法很(hen)多,通(tong)常按(an)(an)固化(hua)前的形態分(fen)(fen)(fen)為固體硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)和(he)液體硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao);按(an)(an)硫化(hua)溫(wen)度(du)分(fen)(fen)(fen)為室溫(wen)硫化(hua)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao),高溫(wen)硫化(hua)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao);按(an)(an)所(suo)用單體的不同,可分(fen)(fen)(fen)為甲基(ji)(ji)乙烯(xi)基(ji)(ji)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao),甲基(ji)(ji)苯(ben)基(ji)(ji)乙烯(xi)基(ji)(ji)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(an)(an)性(xing)能(neng)和(he)用途的不同又可分(fen)(fen)(fen)為通(tong)用型(xing)(xing)、超耐(nai)低溫(wen)型(xing)(xing)、超耐(nai)高溫(wen)型(xing)(xing)、高強力型(xing)(xing)、耐(nai)油型(xing)(xing)、醫(yi)用型(xing)(xing)等等。
發展史
硅(gui)(gui)(gui)橡(xiang)膠(jiao)早期是由美國(guo)(guo)(guo)以三氯(lv)(lv)化(hua)鐵為催化(hua)劑合成的(de)(de)。1945年(nian),硅(gui)(gui)(gui)橡(xiang)膠(jiao)產(chan)(chan)品(pin)問世。1948年(nian),采(cai)用高比(bi)表面積(ji)的(de)(de)氣相法(fa)白炭黑補強的(de)(de)硅(gui)(gui)(gui)橡(xiang)膠(jiao)研(yan)制成功,使硅(gui)(gui)(gui)橡(xiang)膠(jiao)的(de)(de)性能(neng)躍升到實(shi)用階段,奠定了(le)現代硅(gui)(gui)(gui)橡(xiang)膠(jiao)生產(chan)(chan)技術(shu)的(de)(de)基(ji)礎。從二(er)甲基(ji)二(er)氯(lv)(lv)硅(gui)(gui)(gui)烷合成開(kai)始(shi)生產(chan)(chan)硅(gui)(gui)(gui)橡(xiang)膠(jiao)的(de)(de)國(guo)(guo)(guo)家有(you)美國(guo)(guo)(guo)。俄羅斯、德國(guo)(guo)(guo)、日本(ben)、韓(han)國(guo)(guo)(guo)和中(zhong)(zhong)國(guo)(guo)(guo)等。中(zhong)(zhong)國(guo)(guo)(guo)硅(gui)(gui)(gui)橡(xiang)膠(jiao)的(de)(de)工業化(hua)研(yan)究(jiu)始(shi)于(yu)1957年(nian),多家研(yan)究(jiu)所和企業陸續開(kai)發出各種硅(gui)(gui)(gui)橡(xiang)膠(jiao)。到2003年(nian)底,中(zhong)(zhong)國(guo)(guo)(guo)硅(gui)(gui)(gui)橡(xiang)膠(jiao)生產(chan)(chan)能(neng)力為135千(qian)噸(dun),其中(zhong)(zhong)高溫膠(jiao)100千(qian)噸(dun)。
高溫硫化硅橡(xiang)膠
高(gao)(gao)溫硫(liu)化(hua)硅橡(xiang)膠是(shi)(shi)指聚硅氧(yang)烷變(bian)成彈性體(ti)的(de)過(guo)程(cheng)是(shi)(shi)經過(guo)高(gao)(gao)溫(110-170℃)硫(liu)化(hua)成型(xing)的(de)。它(ta)主要以高(gao)(gao)分子量的(de)聚甲基乙烯基硅氧(yang)烷為生膠,混入補強(qiang)填料、硫(liu)化(hua)劑等,在(zai)加(jia)(jia)熱加(jia)(jia)壓下硫(liu)化(hua)成彈性體(ti)。硅橡(xiang)膠的(de)補強(qiang)主要是(shi)(shi)各種(zhong)類型(xing)的(de)白炭黑,可使硫(liu)化(hua)膠的(de)強(qiang)度增加(jia)(jia)數十倍。有(you)(you)時為了降(jiang)低成本或(huo)改善膠料性能及(ji)賦(fu)予硫(liu)化(hua)膠各種(zhong)特殊的(de)性能,也加(jia)(jia)入相應(ying)(ying)的(de)各種(zhong)添加(jia)(jia)劑。硫(liu)化(hua)劑是(shi)(shi)各種(zhong)有(you)(you)機過(guo)氧(yang)化(hua)物或(huo)加(jia)(jia)成反(fan)應(ying)(ying)催化(hua)劑。
加工成(cheng)型方法如圖所(suo)示。一次(ci)硫(liu)化(hua)的(de)目的(de)是(shi)進(jin)行(xing)高(gao)分(fen)(fen)子鏈的(de)交(jiao)聯反應(ying);二次(ci)硫(liu)化(hua)的(de)目的(de)是(shi)進(jin)行(xing)補充(chong)交(jiao)聯、驅(qu)除硫(liu)化(hua)劑分(fen)(fen)解產物(wu)和(he)其他揮發性(xing)化(hua)合(he)物(wu)以穩定硫(liu)化(hua)膠的(de)各項性(xing)能(neng)。常用(yong)的(de)設備有開放(fang)式煉(lian)膠機(ji)、捏合(he)機(ji)及真(zhen)空密煉(lian)機(ji)。
主要(yao)性能
(1)高(gao)(gao)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)顯著的(de)(de)(de)特征是(shi)高(gao)(gao)溫(wen)(wen)穩定(ding)(ding)性(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然常(chang)溫(wen)(wen)下硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)強度(du)(du)僅是(shi)天(tian)然橡(xiang)(xiang)膠(jiao)(jiao)(jiao)或某些(xie)合(he)成橡(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)一半,但在(zai)200℃以上(shang)的(de)(de)(de)高(gao)(gao)溫(wen)(wen)環境下,硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)保(bao)持一定(ding)(ding)的(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和表面硬度(du)(du),且(qie)力(li)學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)無(wu)(wu)明顯變(bian)化(hua)(hua)。(2)低溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)玻璃化(hua)(hua)溫(wen)(wen)度(du)(du)一般為-70~-50℃,特殊配方可達-100℃,表明其低溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)(you)異。這對(dui)航空、宇航工(gong)業(ye)的(de)(de)(de)意義重(zhong)大。(3)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)中Si-O-Si鍵對(dui)氧(yang)、臭氧(yang)及紫外線等十(shi)分(fen)穩定(ding)(ding),在(zai)不加任何添加劑的(de)(de)(de)情況下,就具有優(you)(you)良的(de)(de)(de)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)具有優(you)(you)異的(de)(de)(de)絕(jue)緣(yuan)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng),耐(nai)電暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)電弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非(fei)常(chang)好。(5)物(wu)理(li)機械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)常(chang)溫(wen)(wen)下的(de)(de)(de)物(wu)理(li)機械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)比通(tong)用(yong)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)差(cha),但在(zai)150℃的(de)(de)(de)高(gao)(gao)溫(wen)(wen)和-50℃的(de)(de)(de)低溫(wen)(wen)下,其物(wu)理(li)機械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)(you)于通(tong)用(yong)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)。(6)耐(nai)油及化(hua)(hua)學試(shi)劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)具有中等的(de)(de)(de)耐(nai)油、耐(nai)溶劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。(7)氣(qi)(qi)體(ti)透(tou)過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。室(shi)溫(wen)(wen)下硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)對(dui)空氣(qi)(qi)、氮、氧(yang)、二氧(yang)化(hua)(hua)碳等氣(qi)(qi)體(ti)的(de)(de)(de)透(tou)氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天(tian)然橡(xiang)(xiang)膠(jiao)(jiao)(jiao)高(gao)(gao)出30-50倍。(8)生理(li)惰(duo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)無(wu)(wu)毒,無(wu)(wu)味,無(wu)(wu)嗅,與人體(ti)組(zu)織不粘連,具有抗凝血(xue)作用(yong),對(dui)肌體(ti)組(zu)織的(de)(de)(de)反(fan)應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)非(fei)常(chang)少。特別(bie)適合(he)作為醫用(yong)材(cai)料。
硅橡(xiang)膠(jiao)的用量(liang)
據(ju)中國汽(qi)(qi)車(che)(che)(che)工(gong)業協會統(tong)計,2012年(nian)(nian),汽(qi)(qi)車(che)(che)(che)產銷分別達(da)到1927.18萬(wan)(wan)輛(liang)和1930.64萬(wan)(wan)輛(liang),同比分別增長(chang)4.63%和4.33%,汽(qi)(qi)車(che)(che)(che)工(gong)業硅橡(xiang)(xiang)膠(jiao)的用(yong)量(liang)約達(da)2.0萬(wan)(wan)t。根據(ju)觀研天下的新研究,增加有機硅材料(liao)在汽(qi)(qi)車(che)(che)(che)零(ling)部(bu)件方面的用(yong)量(liang),可以(yi)大(da)幅度提高(gao)汽(qi)(qi)車(che)(che)(che)的安全性能,因此,汽(qi)(qi)車(che)(che)(che)產量(liang)和單(dan)車(che)(che)(che)用(yong)量(liang)水平的提高(gao)都將(jiang)推動汽(qi)(qi)車(che)(che)(che)工(gong)業對硅橡(xiang)(xiang)膠(jiao)需求的增加。國家鼓勵自主(zhu)品(pin)(pin)牌的汽(qi)(qi)車(che)(che)(che)發(fa)展,關鍵(jian)汽(qi)(qi)車(che)(che)(che)零(ling)部(bu)件實(shi)現自主(zhu)化,《2012年(nian)(nian)度黨政(zheng)(zheng)機關公務用(yong)車(che)(che)(che)選用(yong)車(che)(che)(che)型(xing)目錄(征(zheng)求意見稿(gao))》為(wei)自主(zhu)品(pin)(pin)牌擴(kuo)大(da)在政(zheng)(zheng)府采購的市場(chang)份額,為(wei)改變目前國內政(zheng)(zheng)府采購以(yi)合資品(pin)(pin)牌產品(pin)(pin)為(wei)主(zhu)的局(ju)面提供了(le)保障。促進自主(zhu)品(pin)(pin)牌發(fa)展,國產汽(qi)(qi)車(che)(che)(che)業的繁(fan)榮將(jiang)為(wei)汽(qi)(qi)車(che)(che)(che)膠(jiao)的應用(yong)提供有力保障。預測未來3年(nian)(nian),我(wo)國室溫硫化硅橡(xiang)(xiang)膠(jiao)在汽(qi)(qi)車(che)(che)(che)行業將(jiang)以(yi)年(nian)(nian)均20%增長(chang)。
此外,硅(gui)(gui)(gui)(gui)(gui)橡膠(jiao)是重要的非(fei)石(shi)(shi)油(you)(you)(you)基(ji)合成(cheng)橡膠(jiao),約(yue)占非(fei)石(shi)(shi)油(you)(you)(you)基(ji)合成(cheng)橡膠(jiao)消費(fei)量的98%。但因為石(shi)(shi)油(you)(you)(you)價(jia)(jia)(jia)格的大(da)幅上漲,同(tong)時(shi)我國在硅(gui)(gui)(gui)(gui)(gui)橡膠(jiao)的關鍵原料有(you)機(ji)硅(gui)(gui)(gui)(gui)(gui)單(dan)體的生(sheng)產(chan)技術方(fang)面取得突破,有(you)機(ji)硅(gui)(gui)(gui)(gui)(gui)單(dan)體的生(sheng)產(chan)技術在2005年前被幾家跨國公司壟斷,但目前我國已發展成(cheng)為全球有(you)機(ji)硅(gui)(gui)(gui)(gui)(gui)單(dan)體第(di)1大(da)國,這(zhe)2個(ge)方(fang)面原因使硅(gui)(gui)(gui)(gui)(gui)橡膠(jiao)的價(jia)(jia)(jia)格從2011年起開(kai)始低于石(shi)(shi)油(you)(you)(you)基(ji)合成(cheng)橡膠(jiao),僅約(yue)為大(da)宗(zong)石(shi)(shi)油(you)(you)(you)基(ji)橡膠(jiao)的80%~90%,成(cheng)為廉(lian)價(jia)(jia)(jia)的合成(cheng)橡膠(jiao),并開(kai)始大(da)規模替代石(shi)(shi)油(you)(you)(you)基(ji)合成(cheng)橡膠(jiao)。這(zhe)將(jiang)極大(da)拓展有(you)機(ji)硅(gui)(gui)(gui)(gui)(gui)產(chan)業的市場空間,同(tong)時(shi)將(jiang)帶動硅(gui)(gui)(gui)(gui)(gui)油(you)(you)(you)、硅(gui)(gui)(gui)(gui)(gui)烷偶聯劑和(he)硅(gui)(gui)(gui)(gui)(gui)樹脂等其他(ta)有(you)機(ji)硅(gui)(gui)(gui)(gui)(gui)產(chan)品的消費(fei)。