
硅橡膠是指主(zhu)鏈由(you)(you)硅(gui)(gui)(gui)和氧(yang)原子交替構成,硅(gui)(gui)(gui)原子上(shang)通(tong)(tong)常(chang)連(lian)有(you)兩個有(you)機(ji)基(ji)(ji)(ji)團的橡(xiang)膠(jiao)(jiao)。普通(tong)(tong)的硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)主(zhu)要(yao)由(you)(you)含(han)甲(jia)基(ji)(ji)(ji)和少量乙烯基(ji)(ji)(ji)的硅(gui)(gui)(gui)氧(yang)鏈節組成。苯(ben)基(ji)(ji)(ji)的引(yin)入(ru)(ru)可提(ti)高(gao)(gao)(gao)硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的耐(nai)(nai)高(gao)(gao)(gao)、低溫(wen)性(xing)(xing)能(neng)(neng)(neng),三氟丙基(ji)(ji)(ji)及(ji)氰基(ji)(ji)(ji)的引(yin)入(ru)(ru)則可提(ti)高(gao)(gao)(gao)硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的耐(nai)(nai)溫(wen)及(ji)耐(nai)(nai)油性(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)耐(nai)(nai)低溫(wen)性(xing)(xing)能(neng)(neng)(neng)良好,一般在-55℃下(xia)仍能(neng)(neng)(neng)工作。引(yin)入(ru)(ru)苯(ben)基(ji)(ji)(ji)后,可達-73℃。硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的耐(nai)(nai)熱性(xing)(xing)能(neng)(neng)(neng)也(ye)很突出(chu),在180℃下(xia)可長(chang)期工作,稍高(gao)(gao)(gao)于200℃也(ye)能(neng)(neng)(neng)承受(shou)數周或更長(chang)時間仍有(you)彈性(xing)(xing),瞬(shun)時可耐(nai)(nai)300℃以上(shang)的高(gao)(gao)(gao)溫(wen)。硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的透氣(qi)性(xing)(xing)好,氧(yang)氣(qi)透過率在合成聚合物中是較高(gao)(gao)(gao)的。此外,硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)還具(ju)有(you)生理惰性(xing)(xing)、不會導致凝血(xue)的突出(chu)特性(xing)(xing),因此在醫用領域應用廣泛。
主要品種
硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)分類的方法很(hen)多(duo),通常按固(gu)化前的形態(tai)分為(wei)固(gu)體(ti)硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)和液體(ti)硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao);按硫化溫(wen)度(du)分為(wei)室溫(wen)硫化硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao),高溫(wen)硫化硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao);按所(suo)用單體(ti)的不(bu)同(tong),可(ke)分為(wei)甲基(ji)乙烯基(ji)硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao),甲基(ji)苯基(ji)乙烯基(ji)硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)、氟(fu)硅(gui)(gui)(gui)(gui)(gui)(gui),腈硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)等;按性能和用途的不(bu)同(tong)又可(ke)分為(wei)通用型、超耐(nai)低(di)溫(wen)型、超耐(nai)高溫(wen)型、高強力(li)型、耐(nai)油(you)型、醫用型等等。
發展史
硅(gui)橡(xiang)膠(jiao)早期是由美(mei)國以三氯化鐵為催化劑合(he)成的。1945年,硅(gui)橡(xiang)膠(jiao)產(chan)品問世。1948年,采用(yong)高(gao)比表面積的氣(qi)相法(fa)白(bai)炭黑補(bu)強(qiang)的硅(gui)橡(xiang)膠(jiao)研制(zhi)成功(gong),使硅(gui)橡(xiang)膠(jiao)的性能躍升到實用(yong)階(jie)段,奠(dian)定了現代硅(gui)橡(xiang)膠(jiao)生產(chan)技術的基礎。從(cong)二甲基二氯硅(gui)烷合(he)成開始生產(chan)硅(gui)橡(xiang)膠(jiao)的國家有美(mei)國。俄羅斯、德(de)國、日本、韓國和(he)中(zhong)國等。中(zhong)國硅(gui)橡(xiang)膠(jiao)的工業(ye)化研究始于1957年,多家研究所和(he)企業(ye)陸(lu)續(xu)開發出各(ge)種硅(gui)橡(xiang)膠(jiao)。到2003年底,中(zhong)國硅(gui)橡(xiang)膠(jiao)生產(chan)能力為135千噸(dun),其(qi)中(zhong)高(gao)溫膠(jiao)100千噸(dun)。
高溫硫化硅橡膠
高溫(wen)硫化(hua)(hua)(hua)硅(gui)(gui)橡膠(jiao)(jiao)是(shi)(shi)指聚硅(gui)(gui)氧(yang)烷變成彈性(xing)體的(de)(de)過(guo)程是(shi)(shi)經過(guo)高溫(wen)(110-170℃)硫化(hua)(hua)(hua)成型的(de)(de)。它主(zhu)要以高分子(zi)量的(de)(de)聚甲基(ji)乙烯基(ji)硅(gui)(gui)氧(yang)烷為(wei)生膠(jiao)(jiao),混入補強填料(liao)、硫化(hua)(hua)(hua)劑(ji)(ji)等,在加(jia)(jia)熱加(jia)(jia)壓(ya)下硫化(hua)(hua)(hua)成彈性(xing)體。硅(gui)(gui)橡膠(jiao)(jiao)的(de)(de)補強主(zhu)要是(shi)(shi)各(ge)(ge)種(zhong)類型的(de)(de)白炭黑,可(ke)使硫化(hua)(hua)(hua)膠(jiao)(jiao)的(de)(de)強度(du)增加(jia)(jia)數十(shi)倍。有時為(wei)了降低成本或改善膠(jiao)(jiao)料(liao)性(xing)能(neng)及賦(fu)予硫化(hua)(hua)(hua)膠(jiao)(jiao)各(ge)(ge)種(zhong)特(te)殊的(de)(de)性(xing)能(neng),也加(jia)(jia)入相應的(de)(de)各(ge)(ge)種(zhong)添加(jia)(jia)劑(ji)(ji)。硫化(hua)(hua)(hua)劑(ji)(ji)是(shi)(shi)各(ge)(ge)種(zhong)有機(ji)過(guo)氧(yang)化(hua)(hua)(hua)物或加(jia)(jia)成反應催化(hua)(hua)(hua)劑(ji)(ji)。
加工成型(xing)方法如圖(tu)所示。一(yi)次(ci)硫(liu)化(hua)(hua)的(de)(de)(de)目的(de)(de)(de)是進行(xing)高分(fen)子鏈的(de)(de)(de)交聯反(fan)應;二次(ci)硫(liu)化(hua)(hua)的(de)(de)(de)目的(de)(de)(de)是進行(xing)補充交聯、驅(qu)除硫(liu)化(hua)(hua)劑分(fen)解(jie)產(chan)物和其他揮發性(xing)化(hua)(hua)合物以穩定(ding)硫(liu)化(hua)(hua)膠的(de)(de)(de)各項(xiang)性(xing)能。常用(yong)的(de)(de)(de)設備有開放(fang)式煉膠機、捏合機及真(zhen)空密煉機。
主要性能
(1)高(gao)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)顯(xian)著的(de)(de)(de)(de)(de)特(te)征是高(gao)溫(wen)(wen)穩定(ding)性(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然常溫(wen)(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)(de)強度(du)(du)僅是天然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)或某(mou)些合成橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)(de)一(yi)半,但在200℃以(yi)上的(de)(de)(de)(de)(de)高(gao)溫(wen)(wen)環(huan)境下(xia)(xia),硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)仍能(neng)(neng)(neng)(neng)保(bao)持一(yi)定(ding)的(de)(de)(de)(de)(de)柔(rou)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),且力學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)無明顯(xian)變化(hua)(hua)。(2)低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)(de)玻璃(li)化(hua)(hua)溫(wen)(wen)度(du)(du)一(yi)般為(wei)(wei)-70~-50℃,特(te)殊配(pei)方(fang)可(ke)達-100℃,表明其(qi)(qi)低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優(you)(you)異。這對(dui)航空(kong)、宇(yu)航工業的(de)(de)(de)(de)(de)意(yi)義重大。(3)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)中(zhong)(zhong)Si-O-Si鍵對(dui)氧(yang)(yang)(yang)、臭氧(yang)(yang)(yang)及(ji)紫外線(xian)等十分(fen)穩定(ding),在不加任何(he)添加劑的(de)(de)(de)(de)(de)情況(kuang)下(xia)(xia),就(jiu)具(ju)有優(you)(you)良的(de)(de)(de)(de)(de)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)具(ju)有優(you)(you)異的(de)(de)(de)(de)(de)絕(jue)緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng),耐(nai)(nai)電(dian)暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)(nai)電(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非常好。(5)物理機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)常溫(wen)(wen)下(xia)(xia)的(de)(de)(de)(de)(de)物理機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)比通用(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)差,但在150℃的(de)(de)(de)(de)(de)高(gao)溫(wen)(wen)和-50℃的(de)(de)(de)(de)(de)低(di)溫(wen)(wen)下(xia)(xia),其(qi)(qi)物理機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優(you)(you)于通用(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)。(6)耐(nai)(nai)油及(ji)化(hua)(hua)學試劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)具(ju)有中(zhong)(zhong)等的(de)(de)(de)(de)(de)耐(nai)(nai)油、耐(nai)(nai)溶(rong)劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。(7)氣(qi)體透(tou)過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。室溫(wen)(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)對(dui)空(kong)氣(qi)、氮、氧(yang)(yang)(yang)、二氧(yang)(yang)(yang)化(hua)(hua)碳等氣(qi)體的(de)(de)(de)(de)(de)透(tou)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)高(gao)出30-50倍。(8)生理惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)無毒,無味,無嗅,與人體組織不粘(zhan)連,具(ju)有抗凝血作用(yong),對(dui)肌體組織的(de)(de)(de)(de)(de)反應(ying)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常少(shao)。特(te)別適合作為(wei)(wei)醫用(yong)材(cai)料(liao)。
硅橡膠的用量
據(ju)中國汽(qi)車(che)(che)工(gong)業(ye)協會(hui)統計,2012年,汽(qi)車(che)(che)產銷分(fen)別(bie)達到1927.18萬(wan)輛和(he)1930.64萬(wan)輛,同比分(fen)別(bie)增(zeng)長(chang)4.63%和(he)4.33%,汽(qi)車(che)(che)工(gong)業(ye)硅(gui)橡(xiang)膠的(de)(de)(de)(de)用(yong)量(liang)約達2.0萬(wan)t。根據(ju)觀研(yan)天下的(de)(de)(de)(de)新研(yan)究,增(zeng)加有(you)機硅(gui)材料在(zai)(zai)汽(qi)車(che)(che)零部件方(fang)面(mian)的(de)(de)(de)(de)用(yong)量(liang),可(ke)以大幅度提(ti)(ti)(ti)高汽(qi)車(che)(che)的(de)(de)(de)(de)安全(quan)性(xing)能,因此,汽(qi)車(che)(che)產量(liang)和(he)單(dan)車(che)(che)用(yong)量(liang)水(shui)平(ping)的(de)(de)(de)(de)提(ti)(ti)(ti)高都(dou)將推動汽(qi)車(che)(che)工(gong)業(ye)對硅(gui)橡(xiang)膠需求(qiu)(qiu)的(de)(de)(de)(de)增(zeng)加。國家鼓勵自(zi)主(zhu)(zhu)品(pin)牌(pai)(pai)的(de)(de)(de)(de)汽(qi)車(che)(che)發展,關鍵汽(qi)車(che)(che)零部件實現自(zi)主(zhu)(zhu)化,《2012年度黨政機關公(gong)務用(yong)車(che)(che)選(xuan)用(yong)車(che)(che)型(xing)目錄(征求(qiu)(qiu)意見稿)》為(wei)(wei)自(zi)主(zhu)(zhu)品(pin)牌(pai)(pai)擴大在(zai)(zai)政府采(cai)購的(de)(de)(de)(de)市(shi)場份(fen)額,為(wei)(wei)改(gai)變目前國內政府采(cai)購以合資品(pin)牌(pai)(pai)產品(pin)為(wei)(wei)主(zhu)(zhu)的(de)(de)(de)(de)局面(mian)提(ti)(ti)(ti)供(gong)(gong)了保障(zhang)。促進自(zi)主(zhu)(zhu)品(pin)牌(pai)(pai)發展,國產汽(qi)車(che)(che)業(ye)的(de)(de)(de)(de)繁榮將為(wei)(wei)汽(qi)車(che)(che)膠的(de)(de)(de)(de)應(ying)用(yong)提(ti)(ti)(ti)供(gong)(gong)有(you)力保障(zhang)。預測(ce)未(wei)來3年,我國室溫硫化硅(gui)橡(xiang)膠在(zai)(zai)汽(qi)車(che)(che)行業(ye)將以年均20%增(zeng)長(chang)。
此外,硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)是重要(yao)的非(fei)石(shi)油(you)基(ji)合(he)成(cheng)(cheng)橡(xiang)膠(jiao)(jiao)(jiao)(jiao),約占非(fei)石(shi)油(you)基(ji)合(he)成(cheng)(cheng)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)消費(fei)量的98%。但(dan)因為(wei)石(shi)油(you)價格(ge)的大幅上漲,同時我國(guo)在硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)的關(guan)鍵(jian)原料(liao)有(you)機硅(gui)(gui)(gui)單體的生產技(ji)術方面取得(de)突破,有(you)機硅(gui)(gui)(gui)單體的生產技(ji)術在2005年前(qian)被(bei)幾家跨國(guo)公司壟斷(duan),但(dan)目前(qian)我國(guo)已發展(zhan)成(cheng)(cheng)為(wei)全球有(you)機硅(gui)(gui)(gui)單體第(di)1大國(guo),這(zhe)2個方面原因使硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)的價格(ge)從2011年起開始低(di)于石(shi)油(you)基(ji)合(he)成(cheng)(cheng)橡(xiang)膠(jiao)(jiao)(jiao)(jiao),僅約為(wei)大宗(zong)石(shi)油(you)基(ji)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)的80%~90%,成(cheng)(cheng)為(wei)廉價的合(he)成(cheng)(cheng)橡(xiang)膠(jiao)(jiao)(jiao)(jiao),并(bing)開始大規(gui)模替代石(shi)油(you)基(ji)合(he)成(cheng)(cheng)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)。這(zhe)將極(ji)大拓展(zhan)有(you)機硅(gui)(gui)(gui)產業(ye)的市場空間(jian),同時將帶動硅(gui)(gui)(gui)油(you)、硅(gui)(gui)(gui)烷偶聯劑和硅(gui)(gui)(gui)樹脂等其他有(you)機硅(gui)(gui)(gui)產品(pin)的消費(fei)。