
硅橡膠是指(zhi)主(zhu)鏈(lian)由(you)硅(gui)和氧原(yuan)子(zi)交(jiao)替(ti)構成,硅(gui)原(yuan)子(zi)上通常連有(you)兩(liang)個(ge)有(you)機基(ji)團(tuan)的(de)橡(xiang)(xiang)膠(jiao)(jiao)。普通的(de)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)主(zhu)要由(you)含甲基(ji)和少量乙烯基(ji)的(de)硅(gui)氧鏈(lian)節組成。苯基(ji)的(de)引入可(ke)(ke)(ke)提(ti)高(gao)(gao)(gao)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)耐(nai)(nai)高(gao)(gao)(gao)、低(di)溫性(xing)(xing)(xing)能(neng),三氟丙(bing)基(ji)及氰(qing)基(ji)的(de)引入則可(ke)(ke)(ke)提(ti)高(gao)(gao)(gao)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)耐(nai)(nai)溫及耐(nai)(nai)油(you)性(xing)(xing)(xing)能(neng)。硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)耐(nai)(nai)低(di)溫性(xing)(xing)(xing)能(neng)良好,一般在-55℃下仍能(neng)工作。引入苯基(ji)后,可(ke)(ke)(ke)達-73℃。硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)耐(nai)(nai)熱(re)性(xing)(xing)(xing)能(neng)也很突出,在180℃下可(ke)(ke)(ke)長(chang)期工作,稍高(gao)(gao)(gao)于200℃也能(neng)承受數(shu)周或更(geng)長(chang)時間仍有(you)彈性(xing)(xing)(xing),瞬時可(ke)(ke)(ke)耐(nai)(nai)300℃以上的(de)高(gao)(gao)(gao)溫。硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)透氣(qi)性(xing)(xing)(xing)好,氧氣(qi)透過率(lv)在合成聚(ju)合物(wu)中是較(jiao)高(gao)(gao)(gao)的(de)。此外,硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)還具有(you)生理惰性(xing)(xing)(xing)、不會導致凝血的(de)突出特性(xing)(xing)(xing),因此在醫(yi)用領域(yu)應用廣泛(fan)。
主要品種
硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)分(fen)(fen)類的(de)(de)(de)方法很多(duo),通(tong)常按固(gu)化前(qian)的(de)(de)(de)形態分(fen)(fen)為(wei)(wei)固(gu)體(ti)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)和(he)液體(ti)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao);按硫(liu)化溫(wen)度分(fen)(fen)為(wei)(wei)室(shi)溫(wen)硫(liu)化硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao),高溫(wen)硫(liu)化硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao);按所用單體(ti)的(de)(de)(de)不(bu)同(tong),可分(fen)(fen)為(wei)(wei)甲(jia)基乙(yi)(yi)烯基硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao),甲(jia)基苯基乙(yi)(yi)烯基硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)、氟硅(gui)(gui)(gui)(gui),腈硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)等(deng)(deng);按性能(neng)和(he)用途的(de)(de)(de)不(bu)同(tong)又可分(fen)(fen)為(wei)(wei)通(tong)用型、超(chao)耐(nai)低溫(wen)型、超(chao)耐(nai)高溫(wen)型、高強力型、耐(nai)油(you)型、醫用型等(deng)(deng)等(deng)(deng)。
發展史
硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)早期(qi)是由美國(guo)以三氯化鐵為催化劑合成(cheng)(cheng)的(de)。1945年(nian)(nian),硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)產品問(wen)世。1948年(nian)(nian),采用(yong)高(gao)比表面積(ji)的(de)氣相(xiang)法白炭黑補強的(de)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)研(yan)(yan)制成(cheng)(cheng)功,使硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)性能躍升到(dao)實用(yong)階段(duan),奠定(ding)了(le)現代硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)生(sheng)產技術(shu)的(de)基礎。從二甲基二氯硅(gui)(gui)烷合成(cheng)(cheng)開始生(sheng)產硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)國(guo)家有美國(guo)。俄羅(luo)斯、德國(guo)、日本、韓國(guo)和中(zhong)(zhong)國(guo)等(deng)。中(zhong)(zhong)國(guo)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)工業(ye)化研(yan)(yan)究始于(yu)1957年(nian)(nian),多家研(yan)(yan)究所(suo)和企業(ye)陸續開發(fa)出各種硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)。到(dao)2003年(nian)(nian)底,中(zhong)(zhong)國(guo)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)生(sheng)產能力為135千(qian)噸,其中(zhong)(zhong)高(gao)溫膠(jiao)(jiao)(jiao)(jiao)(jiao)100千(qian)噸。
高溫硫化硅橡膠
高(gao)溫硫(liu)(liu)化(hua)(hua)硅橡(xiang)膠(jiao)(jiao)是(shi)指聚硅氧烷變成(cheng)彈(dan)性體的(de)過(guo)程是(shi)經過(guo)高(gao)溫(110-170℃)硫(liu)(liu)化(hua)(hua)成(cheng)型(xing)的(de)。它主要以高(gao)分子量(liang)的(de)聚甲基(ji)乙烯基(ji)硅氧烷為(wei)生膠(jiao)(jiao),混入補(bu)強(qiang)填(tian)料(liao)、硫(liu)(liu)化(hua)(hua)劑(ji)等,在加(jia)(jia)(jia)熱加(jia)(jia)(jia)壓下硫(liu)(liu)化(hua)(hua)成(cheng)彈(dan)性體。硅橡(xiang)膠(jiao)(jiao)的(de)補(bu)強(qiang)主要是(shi)各(ge)種類型(xing)的(de)白炭黑(hei),可使(shi)硫(liu)(liu)化(hua)(hua)膠(jiao)(jiao)的(de)強(qiang)度增加(jia)(jia)(jia)數十倍(bei)。有時為(wei)了降低成(cheng)本或改善膠(jiao)(jiao)料(liao)性能(neng)及賦予硫(liu)(liu)化(hua)(hua)膠(jiao)(jiao)各(ge)種特(te)殊的(de)性能(neng),也(ye)加(jia)(jia)(jia)入相應(ying)的(de)各(ge)種添(tian)加(jia)(jia)(jia)劑(ji)。硫(liu)(liu)化(hua)(hua)劑(ji)是(shi)各(ge)種有機過(guo)氧化(hua)(hua)物或加(jia)(jia)(jia)成(cheng)反應(ying)催化(hua)(hua)劑(ji)。
加工成(cheng)型方法如圖(tu)所(suo)示(shi)。一次(ci)硫化(hua)(hua)的目的是進行(xing)(xing)高(gao)分子鏈的交聯反應;二次(ci)硫化(hua)(hua)的目的是進行(xing)(xing)補充交聯、驅除(chu)硫化(hua)(hua)劑分解產物(wu)和(he)其他揮發性化(hua)(hua)合物(wu)以穩(wen)定硫化(hua)(hua)膠的各項性能。常用的設備有開放(fang)式煉膠機(ji)、捏合機(ji)及(ji)真(zhen)空密煉機(ji)。
主要性能
(1)高(gao)溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅橡(xiang)(xiang)膠顯(xian)著的(de)特(te)征是高(gao)溫(wen)(wen)(wen)(wen)穩定(ding)(ding)性(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然(ran)常溫(wen)(wen)(wen)(wen)下硅橡(xiang)(xiang)膠的(de)強度(du)僅是天(tian)然(ran)橡(xiang)(xiang)膠或某些合(he)成(cheng)橡(xiang)(xiang)膠的(de)一半(ban),但(dan)在(zai)200℃以上的(de)高(gao)溫(wen)(wen)(wen)(wen)環境下,硅橡(xiang)(xiang)膠仍能(neng)(neng)(neng)(neng)保持一定(ding)(ding)的(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈(dan)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和表(biao)面硬度(du),且(qie)力學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)無(wu)明(ming)顯(xian)變化。(2)低(di)(di)溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)硅橡(xiang)(xiang)膠的(de)玻璃化溫(wen)(wen)(wen)(wen)度(du)一般為(wei)-70~-50℃,特(te)殊配方可(ke)達-100℃,表(biao)明(ming)其(qi)低(di)(di)溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優(you)異。這對航空、宇航工業的(de)意義重(zhong)大。(3)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅橡(xiang)(xiang)膠中(zhong)Si-O-Si鍵對氧、臭(chou)氧及紫外線等(deng)十分(fen)穩定(ding)(ding),在(zai)不加任何添加劑(ji)的(de)情況下,就具(ju)有優(you)良(liang)的(de)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅橡(xiang)(xiang)膠具(ju)有優(you)異的(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng),耐(nai)電(dian)暈(yun)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)電(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非(fei)常好。(5)物理機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅橡(xiang)(xiang)膠常溫(wen)(wen)(wen)(wen)下的(de)物理機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)比(bi)通(tong)用(yong)橡(xiang)(xiang)膠差,但(dan)在(zai)150℃的(de)高(gao)溫(wen)(wen)(wen)(wen)和-50℃的(de)低(di)(di)溫(wen)(wen)(wen)(wen)下,其(qi)物理機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優(you)于通(tong)用(yong)橡(xiang)(xiang)膠。(6)耐(nai)油及化學試劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)硅橡(xiang)(xiang)膠具(ju)有中(zhong)等(deng)的(de)耐(nai)油、耐(nai)溶劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。(7)氣(qi)(qi)(qi)體(ti)透過(guo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。室溫(wen)(wen)(wen)(wen)下硅橡(xiang)(xiang)膠對空氣(qi)(qi)(qi)、氮、氧、二(er)氧化碳等(deng)氣(qi)(qi)(qi)體(ti)的(de)透氣(qi)(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)比(bi)天(tian)然(ran)橡(xiang)(xiang)膠高(gao)出30-50倍。(8)生(sheng)理惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅橡(xiang)(xiang)膠無(wu)毒,無(wu)味,無(wu)嗅,與人(ren)體(ti)組織不粘連,具(ju)有抗凝(ning)血作用(yong),對肌體(ti)組織的(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)非(fei)常少。特(te)別(bie)適合(he)作為(wei)醫(yi)用(yong)材料(liao)。
硅橡膠的用量
據(ju)(ju)中國(guo)(guo)汽(qi)(qi)(qi)車(che)(che)(che)(che)工(gong)(gong)業協會統(tong)計,2012年,汽(qi)(qi)(qi)車(che)(che)(che)(che)產(chan)(chan)銷分別達到1927.18萬(wan)輛和1930.64萬(wan)輛,同(tong)比分別增(zeng)(zeng)長(chang)4.63%和4.33%,汽(qi)(qi)(qi)車(che)(che)(che)(che)工(gong)(gong)業硅(gui)(gui)橡膠的(de)(de)(de)(de)用(yong)量(liang)約達2.0萬(wan)t。根據(ju)(ju)觀(guan)研天下的(de)(de)(de)(de)新(xin)研究(jiu),增(zeng)(zeng)加有(you)機(ji)硅(gui)(gui)材料在(zai)汽(qi)(qi)(qi)車(che)(che)(che)(che)零部件(jian)方面的(de)(de)(de)(de)用(yong)量(liang),可以(yi)大幅度提(ti)高汽(qi)(qi)(qi)車(che)(che)(che)(che)的(de)(de)(de)(de)安全(quan)性能(neng),因(yin)此,汽(qi)(qi)(qi)車(che)(che)(che)(che)產(chan)(chan)量(liang)和單車(che)(che)(che)(che)用(yong)量(liang)水平的(de)(de)(de)(de)提(ti)高都將(jiang)(jiang)推動(dong)汽(qi)(qi)(qi)車(che)(che)(che)(che)工(gong)(gong)業對(dui)硅(gui)(gui)橡膠需求的(de)(de)(de)(de)增(zeng)(zeng)加。國(guo)(guo)家鼓勵(li)自主品牌的(de)(de)(de)(de)汽(qi)(qi)(qi)車(che)(che)(che)(che)發(fa)展,關(guan)鍵汽(qi)(qi)(qi)車(che)(che)(che)(che)零部件(jian)實現自主化(hua),《2012年度黨政機(ji)關(guan)公(gong)務用(yong)車(che)(che)(che)(che)選用(yong)車(che)(che)(che)(che)型(xing)目(mu)錄(征求意見(jian)稿)》為(wei)(wei)自主品牌擴大在(zai)政府采(cai)購(gou)的(de)(de)(de)(de)市場(chang)份額(e),為(wei)(wei)改(gai)變目(mu)前國(guo)(guo)內政府采(cai)購(gou)以(yi)合資品牌產(chan)(chan)品為(wei)(wei)主的(de)(de)(de)(de)局面提(ti)供(gong)(gong)了保障。促(cu)進自主品牌發(fa)展,國(guo)(guo)產(chan)(chan)汽(qi)(qi)(qi)車(che)(che)(che)(che)業的(de)(de)(de)(de)繁榮將(jiang)(jiang)為(wei)(wei)汽(qi)(qi)(qi)車(che)(che)(che)(che)膠的(de)(de)(de)(de)應用(yong)提(ti)供(gong)(gong)有(you)力保障。預測未來3年,我國(guo)(guo)室溫硫化(hua)硅(gui)(gui)橡膠在(zai)汽(qi)(qi)(qi)車(che)(che)(che)(che)行業將(jiang)(jiang)以(yi)年均20%增(zeng)(zeng)長(chang)。
此外,硅(gui)(gui)橡(xiang)(xiang)膠是重要的(de)(de)非石(shi)油(you)(you)基合(he)(he)成(cheng)(cheng)橡(xiang)(xiang)膠,約占非石(shi)油(you)(you)基合(he)(he)成(cheng)(cheng)橡(xiang)(xiang)膠消費量(liang)的(de)(de)98%。但因(yin)為石(shi)油(you)(you)價格(ge)(ge)的(de)(de)大幅上漲,同(tong)時我國(guo)在硅(gui)(gui)橡(xiang)(xiang)膠的(de)(de)關鍵(jian)原料有(you)機(ji)硅(gui)(gui)單(dan)體的(de)(de)生(sheng)產技術方(fang)面取得突破,有(you)機(ji)硅(gui)(gui)單(dan)體的(de)(de)生(sheng)產技術在2005年(nian)前(qian)被(bei)幾家跨國(guo)公司壟斷,但目前(qian)我國(guo)已發展成(cheng)(cheng)為全(quan)球有(you)機(ji)硅(gui)(gui)單(dan)體第(di)1大國(guo),這2個(ge)方(fang)面原因(yin)使(shi)硅(gui)(gui)橡(xiang)(xiang)膠的(de)(de)價格(ge)(ge)從2011年(nian)起開始(shi)低于(yu)石(shi)油(you)(you)基合(he)(he)成(cheng)(cheng)橡(xiang)(xiang)膠,僅約為大宗(zong)石(shi)油(you)(you)基橡(xiang)(xiang)膠的(de)(de)80%~90%,成(cheng)(cheng)為廉價的(de)(de)合(he)(he)成(cheng)(cheng)橡(xiang)(xiang)膠,并開始(shi)大規模替代石(shi)油(you)(you)基合(he)(he)成(cheng)(cheng)橡(xiang)(xiang)膠。這將極(ji)大拓展有(you)機(ji)硅(gui)(gui)產業的(de)(de)市場(chang)空間,同(tong)時將帶(dai)動硅(gui)(gui)油(you)(you)、硅(gui)(gui)烷偶聯劑和硅(gui)(gui)樹脂等其他(ta)有(you)機(ji)硅(gui)(gui)產品的(de)(de)消費。