
硅橡膠是(shi)指主(zhu)鏈由硅(gui)和氧(yang)原子交替構(gou)成,硅(gui)原子上(shang)通常連有兩個有機基(ji)團的(de)(de)(de)(de)(de)橡(xiang)(xiang)(xiang)膠(jiao)。普通的(de)(de)(de)(de)(de)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)主(zhu)要由含甲(jia)基(ji)和少量乙烯基(ji)的(de)(de)(de)(de)(de)硅(gui)氧(yang)鏈節組(zu)成。苯基(ji)的(de)(de)(de)(de)(de)引入可提高(gao)(gao)(gao)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)(de)耐(nai)高(gao)(gao)(gao)、低溫(wen)性(xing)(xing)能(neng),三氟丙基(ji)及(ji)氰基(ji)的(de)(de)(de)(de)(de)引入則可提高(gao)(gao)(gao)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)(de)耐(nai)溫(wen)及(ji)耐(nai)油性(xing)(xing)能(neng)。硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)耐(nai)低溫(wen)性(xing)(xing)能(neng)良好(hao),一般(ban)在(zai)-55℃下(xia)仍能(neng)工作(zuo)。引入苯基(ji)后,可達-73℃。硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)(de)耐(nai)熱性(xing)(xing)能(neng)也很突出(chu),在(zai)180℃下(xia)可長期工作(zuo),稍高(gao)(gao)(gao)于200℃也能(neng)承受數周或更(geng)長時間仍有彈性(xing)(xing),瞬時可耐(nai)300℃以上(shang)的(de)(de)(de)(de)(de)高(gao)(gao)(gao)溫(wen)。硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)(de)透(tou)氣性(xing)(xing)好(hao),氧(yang)氣透(tou)過(guo)率在(zai)合成聚合物中是(shi)較高(gao)(gao)(gao)的(de)(de)(de)(de)(de)。此外,硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)還具有生理(li)惰性(xing)(xing)、不會導(dao)致凝(ning)血的(de)(de)(de)(de)(de)突出(chu)特性(xing)(xing),因此在(zai)醫用領域(yu)應用廣泛。
主要品種
硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)分(fen)類(lei)的(de)方法很多,通常(chang)按固(gu)化前的(de)形(xing)態(tai)分(fen)為(wei)固(gu)體(ti)硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)和(he)液體(ti)硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao);按硫(liu)化溫(wen)(wen)度分(fen)為(wei)室溫(wen)(wen)硫(liu)化硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao),高(gao)溫(wen)(wen)硫(liu)化硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao);按所用(yong)單體(ti)的(de)不同(tong),可分(fen)為(wei)甲基乙烯(xi)基硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao),甲基苯(ben)基乙烯(xi)基硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)、氟硅(gui),腈(jing)硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)等(deng);按性能和(he)用(yong)途(tu)的(de)不同(tong)又可分(fen)為(wei)通用(yong)型、超(chao)耐(nai)低溫(wen)(wen)型、超(chao)耐(nai)高(gao)溫(wen)(wen)型、高(gao)強力型、耐(nai)油型、醫用(yong)型等(deng)等(deng)。
發展史
硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)早期(qi)是由美國(guo)(guo)以三(san)氯(lv)(lv)化(hua)鐵為催化(hua)劑合成的(de)(de)(de)。1945年,硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)產(chan)品問世。1948年,采用高(gao)比表面(mian)積(ji)的(de)(de)(de)氣相法白炭黑補強的(de)(de)(de)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)研制成功,使硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)性能(neng)躍升(sheng)到實用階段,奠定了現代硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)生產(chan)技(ji)術(shu)的(de)(de)(de)基礎。從二(er)甲基二(er)氯(lv)(lv)硅(gui)(gui)(gui)烷(wan)合成開始(shi)生產(chan)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)國(guo)(guo)家(jia)有美國(guo)(guo)。俄羅斯(si)、德國(guo)(guo)、日本、韓(han)國(guo)(guo)和中(zhong)(zhong)國(guo)(guo)等。中(zhong)(zhong)國(guo)(guo)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)工業化(hua)研究(jiu)(jiu)始(shi)于1957年,多家(jia)研究(jiu)(jiu)所和企業陸續開發出各種硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)。到2003年底,中(zhong)(zhong)國(guo)(guo)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)生產(chan)能(neng)力為135千噸,其(qi)中(zhong)(zhong)高(gao)溫膠(jiao)100千噸。
高溫硫化硅橡膠
高溫硫(liu)(liu)(liu)化(hua)硅橡(xiang)膠(jiao)是(shi)(shi)指聚硅氧烷變成彈性(xing)(xing)(xing)體(ti)的(de)(de)(de)過(guo)程是(shi)(shi)經過(guo)高溫(110-170℃)硫(liu)(liu)(liu)化(hua)成型的(de)(de)(de)。它主(zhu)要(yao)以高分子量的(de)(de)(de)聚甲基(ji)乙(yi)烯(xi)基(ji)硅氧烷為生膠(jiao),混入(ru)補強(qiang)填料(liao)、硫(liu)(liu)(liu)化(hua)劑(ji)等(deng),在加(jia)(jia)(jia)熱加(jia)(jia)(jia)壓下硫(liu)(liu)(liu)化(hua)成彈性(xing)(xing)(xing)體(ti)。硅橡(xiang)膠(jiao)的(de)(de)(de)補強(qiang)主(zhu)要(yao)是(shi)(shi)各種(zhong)類(lei)型的(de)(de)(de)白炭黑,可使硫(liu)(liu)(liu)化(hua)膠(jiao)的(de)(de)(de)強(qiang)度增(zeng)加(jia)(jia)(jia)數(shu)十倍。有時(shi)為了降(jiang)低成本或改善膠(jiao)料(liao)性(xing)(xing)(xing)能(neng)及賦(fu)予硫(liu)(liu)(liu)化(hua)膠(jiao)各種(zhong)特殊(shu)的(de)(de)(de)性(xing)(xing)(xing)能(neng),也加(jia)(jia)(jia)入(ru)相應(ying)的(de)(de)(de)各種(zhong)添加(jia)(jia)(jia)劑(ji)。硫(liu)(liu)(liu)化(hua)劑(ji)是(shi)(shi)各種(zhong)有機過(guo)氧化(hua)物或加(jia)(jia)(jia)成反應(ying)催化(hua)劑(ji)。
加(jia)工(gong)成(cheng)型(xing)方法如圖所示。一次(ci)(ci)硫(liu)(liu)化的目的是進行高分子鏈的交聯反應;二次(ci)(ci)硫(liu)(liu)化的目的是進行補充交聯、驅除硫(liu)(liu)化劑分解產物和(he)其(qi)他(ta)揮發性化合(he)物以(yi)穩定硫(liu)(liu)化膠(jiao)的各(ge)項性能(neng)。常用(yong)的設備有開放式煉(lian)膠(jiao)機、捏合(he)機及真空密煉(lian)機。
主要性能
(1)高溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)顯著的特(te)(te)征是高溫(wen)穩(wen)定(ding)性(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖(sui)然(ran)常(chang)溫(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的強度僅是天然(ran)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)或(huo)某些合(he)成橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的一(yi)(yi)半,但在200℃以上的高溫(wen)環(huan)境(jing)下(xia)(xia),硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)保持一(yi)(yi)定(ding)的柔韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)表面硬度,且力學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)無明顯變(bian)化。(2)低(di)溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的玻(bo)璃化溫(wen)度一(yi)(yi)般為-70~-50℃,特(te)(te)殊配方可達-100℃,表明其(qi)低(di)溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)異。這(zhe)對(dui)航空、宇航工業(ye)的意義重(zhong)大。(3)耐候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)中(zhong)Si-O-Si鍵(jian)對(dui)氧(yang)(yang)、臭氧(yang)(yang)及(ji)紫(zi)外線等十分穩(wen)定(ding),在不加(jia)任(ren)何(he)添加(jia)劑的情況下(xia)(xia),就具(ju)有(you)(you)優(you)良的耐候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電氣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)有(you)(you)優(you)異的絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng),耐電暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)耐電弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非(fei)常(chang)好(hao)。(5)物(wu)理(li)(li)機械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)常(chang)溫(wen)下(xia)(xia)的物(wu)理(li)(li)機械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)比(bi)通(tong)(tong)用橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)差,但在150℃的高溫(wen)和(he)-50℃的低(di)溫(wen)下(xia)(xia),其(qi)物(wu)理(li)(li)機械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)于通(tong)(tong)用橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。(6)耐油(you)及(ji)化學試劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)(tong)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)有(you)(you)中(zhong)等的耐油(you)、耐溶(rong)劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。(7)氣體(ti)(ti)透(tou)過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。室溫(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)對(dui)空氣、氮、氧(yang)(yang)、二氧(yang)(yang)化碳等氣體(ti)(ti)的透(tou)氣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)比(bi)天然(ran)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)高出30-50倍。(8)生理(li)(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)無毒,無味(wei),無嗅,與人(ren)體(ti)(ti)組(zu)織不粘連,具(ju)有(you)(you)抗凝血作用,對(dui)肌體(ti)(ti)組(zu)織的反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)非(fei)常(chang)少。特(te)(te)別適合(he)作為醫用材(cai)料。
硅橡膠的用量
據中國(guo)(guo)汽(qi)(qi)車(che)工(gong)(gong)業(ye)協會(hui)統計,2012年,汽(qi)(qi)車(che)產銷分(fen)別(bie)達到1927.18萬(wan)輛和1930.64萬(wan)輛,同比分(fen)別(bie)增(zeng)長(chang)4.63%和4.33%,汽(qi)(qi)車(che)工(gong)(gong)業(ye)硅(gui)橡膠(jiao)(jiao)的(de)(de)用(yong)(yong)(yong)量(liang)約達2.0萬(wan)t。根據觀研天下的(de)(de)新(xin)研究,增(zeng)加(jia)有機硅(gui)材料在汽(qi)(qi)車(che)零(ling)部件(jian)方面的(de)(de)用(yong)(yong)(yong)量(liang),可(ke)以大幅度提(ti)高汽(qi)(qi)車(che)的(de)(de)安全(quan)性(xing)能,因(yin)此,汽(qi)(qi)車(che)產量(liang)和單車(che)用(yong)(yong)(yong)量(liang)水平的(de)(de)提(ti)高都(dou)將推動汽(qi)(qi)車(che)工(gong)(gong)業(ye)對(dui)硅(gui)橡膠(jiao)(jiao)需求的(de)(de)增(zeng)加(jia)。國(guo)(guo)家鼓勵自(zi)(zi)主(zhu)(zhu)品牌的(de)(de)汽(qi)(qi)車(che)發展(zhan)(zhan),關(guan)鍵(jian)汽(qi)(qi)車(che)零(ling)部件(jian)實現自(zi)(zi)主(zhu)(zhu)化(hua)(hua),《2012年度黨政機關(guan)公務用(yong)(yong)(yong)車(che)選用(yong)(yong)(yong)車(che)型目錄(征求意(yi)見(jian)稿(gao))》為自(zi)(zi)主(zhu)(zhu)品牌擴大在政府采購(gou)的(de)(de)市場份額,為改變(bian)目前國(guo)(guo)內政府采購(gou)以合資(zi)品牌產品為主(zhu)(zhu)的(de)(de)局面提(ti)供(gong)了保(bao)障(zhang)。促進自(zi)(zi)主(zhu)(zhu)品牌發展(zhan)(zhan),國(guo)(guo)產汽(qi)(qi)車(che)業(ye)的(de)(de)繁榮(rong)將為汽(qi)(qi)車(che)膠(jiao)(jiao)的(de)(de)應用(yong)(yong)(yong)提(ti)供(gong)有力保(bao)障(zhang)。預(yu)測未來3年,我(wo)國(guo)(guo)室溫硫(liu)化(hua)(hua)硅(gui)橡膠(jiao)(jiao)在汽(qi)(qi)車(che)行業(ye)將以年均20%增(zeng)長(chang)。
此(ci)外,硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)是重要的(de)(de)(de)(de)非石(shi)(shi)油基(ji)(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao),約占非石(shi)(shi)油基(ji)(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)消(xiao)費量的(de)(de)(de)(de)98%。但因為石(shi)(shi)油價格的(de)(de)(de)(de)大幅(fu)上漲,同時我國在(zai)硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)關鍵(jian)原(yuan)料(liao)有(you)機(ji)(ji)硅(gui)單體(ti)(ti)的(de)(de)(de)(de)生產(chan)技(ji)術方面取得(de)突破,有(you)機(ji)(ji)硅(gui)單體(ti)(ti)的(de)(de)(de)(de)生產(chan)技(ji)術在(zai)2005年(nian)前被幾家(jia)跨國公司壟斷,但目前我國已發展成(cheng)(cheng)(cheng)為全球有(you)機(ji)(ji)硅(gui)單體(ti)(ti)第1大國,這(zhe)(zhe)2個方面原(yuan)因使硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)價格從2011年(nian)起開始(shi)低于石(shi)(shi)油基(ji)(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao),僅約為大宗石(shi)(shi)油基(ji)(ji)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)80%~90%,成(cheng)(cheng)(cheng)為廉價的(de)(de)(de)(de)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao),并開始(shi)大規模(mo)替代石(shi)(shi)油基(ji)(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。這(zhe)(zhe)將極大拓展有(you)機(ji)(ji)硅(gui)產(chan)業的(de)(de)(de)(de)市場空間,同時將帶動硅(gui)油、硅(gui)烷偶聯劑和硅(gui)樹脂等其他有(you)機(ji)(ji)硅(gui)產(chan)品(pin)的(de)(de)(de)(de)消(xiao)費。