
硅橡膠是指(zhi)主鏈(lian)由硅(gui)和(he)氧(yang)原子交替構成(cheng)(cheng),硅(gui)原子上通常(chang)連有(you)兩個有(you)機基(ji)(ji)團的(de)(de)(de)(de)橡(xiang)膠(jiao)(jiao)。普通的(de)(de)(de)(de)硅(gui)橡(xiang)膠(jiao)(jiao)主要由含甲基(ji)(ji)和(he)少量乙烯基(ji)(ji)的(de)(de)(de)(de)硅(gui)氧(yang)鏈(lian)節組(zu)成(cheng)(cheng)。苯基(ji)(ji)的(de)(de)(de)(de)引入(ru)(ru)(ru)可(ke)提高(gao)(gao)硅(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)耐高(gao)(gao)、低(di)溫性(xing)(xing)(xing)能(neng)(neng)(neng),三氟丙基(ji)(ji)及氰基(ji)(ji)的(de)(de)(de)(de)引入(ru)(ru)(ru)則可(ke)提高(gao)(gao)硅(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)耐溫及耐油性(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)橡(xiang)膠(jiao)(jiao)耐低(di)溫性(xing)(xing)(xing)能(neng)(neng)(neng)良好,一般(ban)在(zai)(zai)-55℃下(xia)仍能(neng)(neng)(neng)工作(zuo)。引入(ru)(ru)(ru)苯基(ji)(ji)后,可(ke)達-73℃。硅(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)耐熱性(xing)(xing)(xing)能(neng)(neng)(neng)也很突(tu)出(chu),在(zai)(zai)180℃下(xia)可(ke)長期工作(zuo),稍高(gao)(gao)于200℃也能(neng)(neng)(neng)承受數周或更長時間仍有(you)彈性(xing)(xing)(xing),瞬時可(ke)耐300℃以上的(de)(de)(de)(de)高(gao)(gao)溫。硅(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)透氣性(xing)(xing)(xing)好,氧(yang)氣透過率(lv)在(zai)(zai)合成(cheng)(cheng)聚合物中是較高(gao)(gao)的(de)(de)(de)(de)。此外,硅(gui)橡(xiang)膠(jiao)(jiao)還具有(you)生理惰性(xing)(xing)(xing)、不(bu)會導致(zhi)凝(ning)血的(de)(de)(de)(de)突(tu)出(chu)特(te)性(xing)(xing)(xing),因此在(zai)(zai)醫用領域應用廣泛。
主要品種
硅橡(xiang)(xiang)膠(jiao)分類的(de)方(fang)法很(hen)多,通(tong)常按固(gu)化(hua)(hua)(hua)前的(de)形態分為(wei)固(gu)體硅橡(xiang)(xiang)膠(jiao)和液(ye)體硅橡(xiang)(xiang)膠(jiao);按硫(liu)化(hua)(hua)(hua)溫(wen)(wen)(wen)度分為(wei)室溫(wen)(wen)(wen)硫(liu)化(hua)(hua)(hua)硅橡(xiang)(xiang)膠(jiao),高(gao)溫(wen)(wen)(wen)硫(liu)化(hua)(hua)(hua)硅橡(xiang)(xiang)膠(jiao);按所用(yong)單體的(de)不同(tong)(tong),可分為(wei)甲基乙烯(xi)基硅橡(xiang)(xiang)膠(jiao),甲基苯基乙烯(xi)基硅橡(xiang)(xiang)膠(jiao)、氟硅,腈(jing)硅橡(xiang)(xiang)膠(jiao)等;按性能和用(yong)途的(de)不同(tong)(tong)又可分為(wei)通(tong)用(yong)型(xing)、超(chao)耐低溫(wen)(wen)(wen)型(xing)、超(chao)耐高(gao)溫(wen)(wen)(wen)型(xing)、高(gao)強(qiang)力型(xing)、耐油型(xing)、醫用(yong)型(xing)等等。
發展史
硅(gui)(gui)(gui)橡膠(jiao)早期是由美國(guo)(guo)以三氯(lv)化鐵為(wei)催化劑(ji)合成(cheng)的(de)。1945年(nian)(nian),硅(gui)(gui)(gui)橡膠(jiao)產(chan)品問世。1948年(nian)(nian),采用高(gao)(gao)比表面積的(de)氣相法白炭黑補強(qiang)的(de)硅(gui)(gui)(gui)橡膠(jiao)研(yan)制成(cheng)功,使硅(gui)(gui)(gui)橡膠(jiao)的(de)性(xing)能(neng)躍升到實用階段,奠定了現代硅(gui)(gui)(gui)橡膠(jiao)生(sheng)產(chan)技術的(de)基礎。從(cong)二甲基二氯(lv)硅(gui)(gui)(gui)烷(wan)合成(cheng)開始生(sheng)產(chan)硅(gui)(gui)(gui)橡膠(jiao)的(de)國(guo)(guo)家有美國(guo)(guo)。俄(e)羅斯、德(de)國(guo)(guo)、日本、韓國(guo)(guo)和中(zhong)國(guo)(guo)等。中(zhong)國(guo)(guo)硅(gui)(gui)(gui)橡膠(jiao)的(de)工業(ye)化研(yan)究始于1957年(nian)(nian),多家研(yan)究所和企業(ye)陸續(xu)開發出各種(zhong)硅(gui)(gui)(gui)橡膠(jiao)。到2003年(nian)(nian)底,中(zhong)國(guo)(guo)硅(gui)(gui)(gui)橡膠(jiao)生(sheng)產(chan)能(neng)力(li)為(wei)135千(qian)噸,其中(zhong)高(gao)(gao)溫(wen)膠(jiao)100千(qian)噸。
高溫硫化硅橡膠
高(gao)溫(wen)硫(liu)(liu)化(hua)硅橡膠(jiao)是(shi)(shi)指聚硅氧(yang)(yang)烷(wan)變成(cheng)(cheng)(cheng)彈(dan)性(xing)(xing)體的過程是(shi)(shi)經過高(gao)溫(wen)(110-170℃)硫(liu)(liu)化(hua)成(cheng)(cheng)(cheng)型(xing)的。它主(zhu)要(yao)以高(gao)分子(zi)量的聚甲(jia)基(ji)乙烯(xi)基(ji)硅氧(yang)(yang)烷(wan)為生膠(jiao),混入補強填料、硫(liu)(liu)化(hua)劑等,在(zai)加(jia)(jia)熱加(jia)(jia)壓(ya)下硫(liu)(liu)化(hua)成(cheng)(cheng)(cheng)彈(dan)性(xing)(xing)體。硅橡膠(jiao)的補強主(zhu)要(yao)是(shi)(shi)各(ge)種類型(xing)的白(bai)炭(tan)黑,可使(shi)硫(liu)(liu)化(hua)膠(jiao)的強度(du)增加(jia)(jia)數十倍(bei)。有時(shi)為了降低成(cheng)(cheng)(cheng)本或改(gai)善膠(jiao)料性(xing)(xing)能(neng)及賦(fu)予硫(liu)(liu)化(hua)膠(jiao)各(ge)種特殊(shu)的性(xing)(xing)能(neng),也加(jia)(jia)入相應的各(ge)種添加(jia)(jia)劑。硫(liu)(liu)化(hua)劑是(shi)(shi)各(ge)種有機(ji)過氧(yang)(yang)化(hua)物或加(jia)(jia)成(cheng)(cheng)(cheng)反(fan)應催化(hua)劑。
加工成(cheng)型方(fang)法如圖所示。一次硫化(hua)的(de)(de)目(mu)的(de)(de)是(shi)進行(xing)高(gao)分子鏈的(de)(de)交聯反應;二次硫化(hua)的(de)(de)目(mu)的(de)(de)是(shi)進行(xing)補充交聯、驅(qu)除硫化(hua)劑分解(jie)產(chan)物和(he)其他揮發性化(hua)合物以穩定硫化(hua)膠(jiao)的(de)(de)各項性能(neng)。常用的(de)(de)設備有開(kai)放式煉膠(jiao)機、捏合機及(ji)真(zhen)空密煉機。
主要性能
(1)高(gao)(gao)(gao)溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)顯著的(de)(de)(de)(de)特征是(shi)高(gao)(gao)(gao)溫(wen)(wen)(wen)(wen)穩定(ding)性(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然(ran)(ran)常溫(wen)(wen)(wen)(wen)下(xia)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)強度僅是(shi)天(tian)(tian)然(ran)(ran)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)或某些合成橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)一(yi)半(ban),但在200℃以(yi)上的(de)(de)(de)(de)高(gao)(gao)(gao)溫(wen)(wen)(wen)(wen)環境下(xia),硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)保持一(yi)定(ding)的(de)(de)(de)(de)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(li)學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)無明(ming)(ming)顯變化(hua)。(2)低溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)玻璃化(hua)溫(wen)(wen)(wen)(wen)度一(yi)般為-70~-50℃,特殊配方可達-100℃,表明(ming)(ming)其(qi)低溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優異。這對航空(kong)、宇(yu)航工業的(de)(de)(de)(de)意義重大(da)。(3)耐(nai)(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵對氧、臭氧及紫外線等十分穩定(ding),在不加(jia)任何(he)添加(jia)劑(ji)(ji)的(de)(de)(de)(de)情況下(xia),就(jiu)具有(you)優良的(de)(de)(de)(de)耐(nai)(nai)(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)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)具有(you)優異的(de)(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng),耐(nai)(nai)(nai)電暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)耐(nai)(nai)(nai)電弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非常好(hao)。(5)物(wu)理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)常溫(wen)(wen)(wen)(wen)下(xia)的(de)(de)(de)(de)物(wu)理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)比通用橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)差,但在150℃的(de)(de)(de)(de)高(gao)(gao)(gao)溫(wen)(wen)(wen)(wen)和(he)-50℃的(de)(de)(de)(de)低溫(wen)(wen)(wen)(wen)下(xia),其(qi)物(wu)理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優于通用橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)(nai)(nai)油及化(hua)學試劑(ji)(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)具有(you)中等的(de)(de)(de)(de)耐(nai)(nai)(nai)油、耐(nai)(nai)(nai)溶劑(ji)(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。(7)氣(qi)(qi)體透過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。室溫(wen)(wen)(wen)(wen)下(xia)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)對空(kong)氣(qi)(qi)、氮、氧、二氧化(hua)碳等氣(qi)(qi)體的(de)(de)(de)(de)透氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天(tian)(tian)然(ran)(ran)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)高(gao)(gao)(gao)出30-50倍(bei)。(8)生理(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)無毒,無味,無嗅(xiu),與人(ren)體組織不粘連,具有(you)抗凝血作用,對肌體組織的(de)(de)(de)(de)反(fan)應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常少。特別適合作為醫(yi)用材料(liao)。
硅橡膠的用量
據中國(guo)汽(qi)(qi)(qi)(qi)車(che)(che)工(gong)(gong)業(ye)協會(hui)統(tong)計,2012年(nian)(nian),汽(qi)(qi)(qi)(qi)車(che)(che)產銷分(fen)別(bie)達到1927.18萬(wan)輛和(he)(he)1930.64萬(wan)輛,同(tong)比分(fen)別(bie)增(zeng)長(chang)4.63%和(he)(he)4.33%,汽(qi)(qi)(qi)(qi)車(che)(che)工(gong)(gong)業(ye)硅橡膠的(de)(de)用(yong)量約達2.0萬(wan)t。根據觀研天下的(de)(de)新研究,增(zeng)加有機硅材料在汽(qi)(qi)(qi)(qi)車(che)(che)零(ling)部件方面的(de)(de)用(yong)量,可以(yi)大幅度提(ti)高(gao)汽(qi)(qi)(qi)(qi)車(che)(che)的(de)(de)安全性能(neng),因此,汽(qi)(qi)(qi)(qi)車(che)(che)產量和(he)(he)單車(che)(che)用(yong)量水平的(de)(de)提(ti)高(gao)都(dou)將推動汽(qi)(qi)(qi)(qi)車(che)(che)工(gong)(gong)業(ye)對硅橡膠需求的(de)(de)增(zeng)加。國(guo)家(jia)鼓勵自主(zhu)品(pin)牌(pai)(pai)(pai)的(de)(de)汽(qi)(qi)(qi)(qi)車(che)(che)發(fa)展,關(guan)鍵汽(qi)(qi)(qi)(qi)車(che)(che)零(ling)部件實現(xian)自主(zhu)化,《2012年(nian)(nian)度黨政機關(guan)公務用(yong)車(che)(che)選(xuan)用(yong)車(che)(che)型(xing)目錄(征求意見稿)》為自主(zhu)品(pin)牌(pai)(pai)(pai)擴大在政府(fu)采購(gou)的(de)(de)市場份額,為改變目前國(guo)內政府(fu)采購(gou)以(yi)合資品(pin)牌(pai)(pai)(pai)產品(pin)為主(zhu)的(de)(de)局(ju)面提(ti)供(gong)(gong)了保障(zhang)(zhang)。促進自主(zhu)品(pin)牌(pai)(pai)(pai)發(fa)展,國(guo)產汽(qi)(qi)(qi)(qi)車(che)(che)業(ye)的(de)(de)繁榮將為汽(qi)(qi)(qi)(qi)車(che)(che)膠的(de)(de)應(ying)用(yong)提(ti)供(gong)(gong)有力保障(zhang)(zhang)。預(yu)測未來3年(nian)(nian),我(wo)國(guo)室溫硫化硅橡膠在汽(qi)(qi)(qi)(qi)車(che)(che)行業(ye)將以(yi)年(nian)(nian)均20%增(zeng)長(chang)。
此外,硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)是重(zhong)要的(de)(de)(de)非(fei)石(shi)油(you)(you)(you)基(ji)(ji)合成(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao),約(yue)(yue)占非(fei)石(shi)油(you)(you)(you)基(ji)(ji)合成(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)消(xiao)費量的(de)(de)(de)98%。但因(yin)為石(shi)油(you)(you)(you)價格的(de)(de)(de)大(da)幅上(shang)漲,同時我國(guo)在硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)關(guan)鍵原(yuan)料有(you)機硅(gui)(gui)(gui)單體的(de)(de)(de)生產(chan)技術方面取(qu)得突破,有(you)機硅(gui)(gui)(gui)單體的(de)(de)(de)生產(chan)技術在2005年前被幾家跨國(guo)公司壟斷,但目(mu)前我國(guo)已(yi)發展成(cheng)為全球有(you)機硅(gui)(gui)(gui)單體第1大(da)國(guo),這2個方面原(yuan)因(yin)使硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)價格從2011年起開始(shi)低(di)于石(shi)油(you)(you)(you)基(ji)(ji)合成(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao),僅約(yue)(yue)為大(da)宗石(shi)油(you)(you)(you)基(ji)(ji)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)80%~90%,成(cheng)為廉價的(de)(de)(de)合成(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao),并開始(shi)大(da)規模替代石(shi)油(you)(you)(you)基(ji)(ji)合成(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)。這將極大(da)拓展有(you)機硅(gui)(gui)(gui)產(chan)業(ye)的(de)(de)(de)市場空(kong)間,同時將帶動硅(gui)(gui)(gui)油(you)(you)(you)、硅(gui)(gui)(gui)烷偶聯(lian)劑(ji)和硅(gui)(gui)(gui)樹脂等其(qi)他有(you)機硅(gui)(gui)(gui)產(chan)品的(de)(de)(de)消(xiao)費。