
硅橡膠是(shi)指主(zhu)鏈由(you)硅(gui)和氧(yang)(yang)原子交替構成,硅(gui)原子上(shang)通(tong)常(chang)連有(you)兩(liang)個(ge)有(you)機基(ji)團的(de)(de)橡膠(jiao)(jiao)(jiao)(jiao)。普通(tong)的(de)(de)硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)主(zhu)要(yao)由(you)含甲基(ji)和少量乙烯基(ji)的(de)(de)硅(gui)氧(yang)(yang)鏈節組成。苯基(ji)的(de)(de)引(yin)(yin)入(ru)可(ke)(ke)(ke)提高(gao)(gao)硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)的(de)(de)耐(nai)(nai)高(gao)(gao)、低溫(wen)性能(neng),三氟丙基(ji)及氰(qing)基(ji)的(de)(de)引(yin)(yin)入(ru)則可(ke)(ke)(ke)提高(gao)(gao)硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)的(de)(de)耐(nai)(nai)溫(wen)及耐(nai)(nai)油性能(neng)。硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)耐(nai)(nai)低溫(wen)性能(neng)良好,一般在(zai)-55℃下仍能(neng)工作(zuo)。引(yin)(yin)入(ru)苯基(ji)后(hou),可(ke)(ke)(ke)達-73℃。硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)的(de)(de)耐(nai)(nai)熱性能(neng)也很突出(chu),在(zai)180℃下可(ke)(ke)(ke)長(chang)期工作(zuo),稍高(gao)(gao)于200℃也能(neng)承受數周或更長(chang)時間仍有(you)彈性,瞬時可(ke)(ke)(ke)耐(nai)(nai)300℃以(yi)上(shang)的(de)(de)高(gao)(gao)溫(wen)。硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)的(de)(de)透(tou)氣性好,氧(yang)(yang)氣透(tou)過率在(zai)合成聚合物(wu)中是(shi)較高(gao)(gao)的(de)(de)。此(ci)外,硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)還(huan)具有(you)生理惰性、不會導(dao)致凝血的(de)(de)突出(chu)特(te)性,因此(ci)在(zai)醫用(yong)領域應用(yong)廣泛。
主要品種
硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)分(fen)類的方(fang)法很多(duo),通常按固化前(qian)的形態分(fen)為固體硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)和液體硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao);按硫(liu)化溫度分(fen)為室(shi)溫硫(liu)化硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao),高(gao)溫硫(liu)化硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao);按所用單體的不同,可分(fen)為甲基(ji)乙(yi)烯(xi)基(ji)硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao),甲基(ji)苯基(ji)乙(yi)烯(xi)基(ji)硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)、氟硅(gui)(gui)(gui),腈硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)等;按性能和用途(tu)的不同又(you)可分(fen)為通用型(xing)(xing)、超耐(nai)低(di)溫型(xing)(xing)、超耐(nai)高(gao)溫型(xing)(xing)、高(gao)強力型(xing)(xing)、耐(nai)油(you)型(xing)(xing)、醫(yi)用型(xing)(xing)等等。
發展史
硅(gui)橡(xiang)膠早期是由美國(guo)以三氯化鐵為催(cui)化劑合成的(de)(de)(de)(de)(de)。1945年(nian)(nian),硅(gui)橡(xiang)膠產(chan)(chan)品問世。1948年(nian)(nian),采用(yong)高(gao)比表面積的(de)(de)(de)(de)(de)氣相法(fa)白(bai)炭(tan)黑補強的(de)(de)(de)(de)(de)硅(gui)橡(xiang)膠研(yan)制成功,使硅(gui)橡(xiang)膠的(de)(de)(de)(de)(de)性能躍升到實(shi)用(yong)階段(duan),奠定了(le)現代硅(gui)橡(xiang)膠生(sheng)(sheng)(sheng)產(chan)(chan)技術的(de)(de)(de)(de)(de)基礎。從(cong)二(er)甲基二(er)氯硅(gui)烷合成開(kai)始生(sheng)(sheng)(sheng)產(chan)(chan)硅(gui)橡(xiang)膠的(de)(de)(de)(de)(de)國(guo)家有美國(guo)。俄(e)羅斯(si)、德國(guo)、日本、韓國(guo)和中(zhong)國(guo)等。中(zhong)國(guo)硅(gui)橡(xiang)膠的(de)(de)(de)(de)(de)工業化研(yan)究(jiu)始于1957年(nian)(nian),多(duo)家研(yan)究(jiu)所和企(qi)業陸續開(kai)發(fa)出各種硅(gui)橡(xiang)膠。到2003年(nian)(nian)底,中(zhong)國(guo)硅(gui)橡(xiang)膠生(sheng)(sheng)(sheng)產(chan)(chan)能力為135千(qian)噸,其中(zhong)高(gao)溫膠100千(qian)噸。
高溫硫化硅橡膠
高(gao)溫硫(liu)化硅(gui)橡(xiang)膠(jiao)(jiao)是(shi)(shi)指(zhi)聚硅(gui)氧(yang)烷變成彈性(xing)體的過程是(shi)(shi)經過高(gao)溫(110-170℃)硫(liu)化成型(xing)的。它(ta)主(zhu)要以高(gao)分(fen)子(zi)量(liang)的聚甲基(ji)(ji)乙(yi)烯基(ji)(ji)硅(gui)氧(yang)烷為生膠(jiao)(jiao),混入補強(qiang)填料、硫(liu)化劑(ji)(ji)等(deng),在加(jia)熱加(jia)壓下(xia)硫(liu)化成彈性(xing)體。硅(gui)橡(xiang)膠(jiao)(jiao)的補強(qiang)主(zhu)要是(shi)(shi)各(ge)種(zhong)(zhong)類型(xing)的白炭黑(hei),可(ke)使硫(liu)化膠(jiao)(jiao)的強(qiang)度增(zeng)加(jia)數十倍。有(you)時為了降低成本或(huo)改善膠(jiao)(jiao)料性(xing)能及(ji)賦予硫(liu)化膠(jiao)(jiao)各(ge)種(zhong)(zhong)特(te)殊(shu)的性(xing)能,也加(jia)入相應的各(ge)種(zhong)(zhong)添(tian)加(jia)劑(ji)(ji)。硫(liu)化劑(ji)(ji)是(shi)(shi)各(ge)種(zhong)(zhong)有(you)機過氧(yang)化物(wu)或(huo)加(jia)成反應催(cui)化劑(ji)(ji)。
加(jia)工(gong)成型方(fang)法(fa)如圖所示。一次硫化(hua)的(de)目的(de)是進(jin)行(xing)高(gao)分子鏈的(de)交(jiao)聯反(fan)應;二(er)次硫化(hua)的(de)目的(de)是進(jin)行(xing)補充交(jiao)聯、驅除硫化(hua)劑分解產物和(he)其他揮發(fa)性化(hua)合物以穩定硫化(hua)膠的(de)各項性能(neng)。常(chang)用(yong)的(de)設備有開放式煉(lian)(lian)膠機、捏合機及(ji)真空密(mi)煉(lian)(lian)機。
主要性能
(1)高溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)顯(xian)著的(de)(de)特征是高溫(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然常溫(wen)下(xia)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)強度僅是天(tian)然橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)或某些合成(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)一半,但在200℃以(yi)上的(de)(de)高溫(wen)環境下(xia),硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)(neng)(neng)(neng)保(bao)持一定的(de)(de)柔(rou)韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)表面硬度,且力學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)無(wu)明顯(xian)變(bian)化(hua)。(2)低(di)溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)玻璃化(hua)溫(wen)度一般為(wei)-70~-50℃,特殊配方可達(da)-100℃,表明其低(di)溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)優(you)異。這對航空、宇航工業(ye)的(de)(de)意(yi)義(yi)重大。(3)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)中Si-O-Si鍵對氧(yang)(yang)、臭氧(yang)(yang)及紫外線等(deng)十分穩定,在不加任何(he)添(tian)加劑(ji)(ji)的(de)(de)情況下(xia),就具有(you)(you)優(you)良的(de)(de)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)(dian)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)具有(you)(you)優(you)異的(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng),耐(nai)電(dian)(dian)暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)耐(nai)電(dian)(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也(ye)非(fei)常好。(5)物(wu)理機(ji)(ji)械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)常溫(wen)下(xia)的(de)(de)物(wu)理機(ji)(ji)械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)比通用(yong)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)差,但在150℃的(de)(de)高溫(wen)和(he)-50℃的(de)(de)低(di)溫(wen)下(xia),其物(wu)理機(ji)(ji)械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)優(you)于通用(yong)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)。(6)耐(nai)油(you)及化(hua)學試劑(ji)(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)具有(you)(you)中等(deng)的(de)(de)耐(nai)油(you)、耐(nai)溶(rong)劑(ji)(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)。(7)氣(qi)體透(tou)過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)(neng)。室溫(wen)下(xia)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)對空氣(qi)、氮(dan)、氧(yang)(yang)、二氧(yang)(yang)化(hua)碳等(deng)氣(qi)體的(de)(de)透(tou)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天(tian)然橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)高出(chu)30-50倍。(8)生理惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)無(wu)毒(du),無(wu)味,無(wu)嗅(xiu),與人體組織不粘連,具有(you)(you)抗凝血作(zuo)用(yong),對肌體組織的(de)(de)反(fan)應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非(fei)常少。特別適合作(zuo)為(wei)醫用(yong)材料。
硅橡膠的用量
據(ju)中(zhong)國(guo)汽(qi)(qi)(qi)車(che)(che)(che)(che)工(gong)業(ye)協會統計,2012年(nian)(nian),汽(qi)(qi)(qi)車(che)(che)(che)(che)產(chan)銷分別(bie)達到1927.18萬(wan)輛(liang)和1930.64萬(wan)輛(liang),同比分別(bie)增(zeng)長4.63%和4.33%,汽(qi)(qi)(qi)車(che)(che)(che)(che)工(gong)業(ye)硅(gui)(gui)(gui)橡(xiang)膠的(de)(de)用量(liang)約達2.0萬(wan)t。根據(ju)觀研(yan)天下的(de)(de)新(xin)研(yan)究,增(zeng)加有(you)機(ji)硅(gui)(gui)(gui)材料在(zai)(zai)汽(qi)(qi)(qi)車(che)(che)(che)(che)零部(bu)件方面的(de)(de)用量(liang),可以大(da)幅度提高汽(qi)(qi)(qi)車(che)(che)(che)(che)的(de)(de)安全性能,因此,汽(qi)(qi)(qi)車(che)(che)(che)(che)產(chan)量(liang)和單車(che)(che)(che)(che)用量(liang)水平的(de)(de)提高都將推動(dong)汽(qi)(qi)(qi)車(che)(che)(che)(che)工(gong)業(ye)對硅(gui)(gui)(gui)橡(xiang)膠需求的(de)(de)增(zeng)加。國(guo)家鼓勵自(zi)主品(pin)牌的(de)(de)汽(qi)(qi)(qi)車(che)(che)(che)(che)發(fa)展,關(guan)鍵(jian)汽(qi)(qi)(qi)車(che)(che)(che)(che)零部(bu)件實現自(zi)主化,《2012年(nian)(nian)度黨(dang)政(zheng)機(ji)關(guan)公務用車(che)(che)(che)(che)選用車(che)(che)(che)(che)型(xing)目錄(征求意見稿)》為自(zi)主品(pin)牌擴大(da)在(zai)(zai)政(zheng)府采購的(de)(de)市(shi)場(chang)份額(e),為改變(bian)目前國(guo)內政(zheng)府采購以合資品(pin)牌產(chan)品(pin)為主的(de)(de)局面提供了保(bao)障。促進自(zi)主品(pin)牌發(fa)展,國(guo)產(chan)汽(qi)(qi)(qi)車(che)(che)(che)(che)業(ye)的(de)(de)繁榮(rong)將為汽(qi)(qi)(qi)車(che)(che)(che)(che)膠的(de)(de)應用提供有(you)力保(bao)障。預(yu)測未來3年(nian)(nian),我國(guo)室溫硫化硅(gui)(gui)(gui)橡(xiang)膠在(zai)(zai)汽(qi)(qi)(qi)車(che)(che)(che)(che)行業(ye)將以年(nian)(nian)均(jun)20%增(zeng)長。
此外,硅(gui)橡(xiang)膠(jiao)(jiao)是重要的(de)非石油(you)(you)(you)(you)基(ji)(ji)合成(cheng)(cheng)(cheng)(cheng)(cheng)橡(xiang)膠(jiao)(jiao),約(yue)占非石油(you)(you)(you)(you)基(ji)(ji)合成(cheng)(cheng)(cheng)(cheng)(cheng)橡(xiang)膠(jiao)(jiao)消費(fei)量(liang)的(de)98%。但因(yin)為(wei)石油(you)(you)(you)(you)價格的(de)大(da)(da)幅上漲,同(tong)時(shi)我國在(zai)硅(gui)橡(xiang)膠(jiao)(jiao)的(de)關鍵(jian)原(yuan)(yuan)料(liao)有(you)機(ji)硅(gui)單體的(de)生產技術方面(mian)取(qu)得突破,有(you)機(ji)硅(gui)單體的(de)生產技術在(zai)2005年前被幾家跨國公司(si)壟斷,但目(mu)前我國已發展(zhan)成(cheng)(cheng)(cheng)(cheng)(cheng)為(wei)全球有(you)機(ji)硅(gui)單體第(di)1大(da)(da)國,這2個(ge)方面(mian)原(yuan)(yuan)因(yin)使硅(gui)橡(xiang)膠(jiao)(jiao)的(de)價格從2011年起開始低于石油(you)(you)(you)(you)基(ji)(ji)合成(cheng)(cheng)(cheng)(cheng)(cheng)橡(xiang)膠(jiao)(jiao),僅約(yue)為(wei)大(da)(da)宗(zong)石油(you)(you)(you)(you)基(ji)(ji)橡(xiang)膠(jiao)(jiao)的(de)80%~90%,成(cheng)(cheng)(cheng)(cheng)(cheng)為(wei)廉(lian)價的(de)合成(cheng)(cheng)(cheng)(cheng)(cheng)橡(xiang)膠(jiao)(jiao),并開始大(da)(da)規模替代石油(you)(you)(you)(you)基(ji)(ji)合成(cheng)(cheng)(cheng)(cheng)(cheng)橡(xiang)膠(jiao)(jiao)。這將(jiang)極(ji)大(da)(da)拓展(zhan)有(you)機(ji)硅(gui)產業的(de)市場空(kong)間,同(tong)時(shi)將(jiang)帶動硅(gui)油(you)(you)(you)(you)、硅(gui)烷(wan)偶聯劑和(he)硅(gui)樹(shu)脂等其(qi)他有(you)機(ji)硅(gui)產品的(de)消費(fei)。