預防中空玻璃失效的措施

　　想要言正常(chang)中空玻(bo)璃的有效使用(yong)時間，必(bi)須從各個環節加以控(kong)制(zhi)、如生產工藝條件、原(yuan)材料選擇、安裝運(yun)輸等。

　　(1)嚴格控制生產環境的濕度

　　生(sheng)產環(huan)境的(de)濕度主要是(shi)影響干(gan)燥(zao)劑(ji)的(de)有效(xiao)吸(xi)(xi)(xi)(xi)附(fu)(fu)(fu)能(neng)(neng)力(li)(li)和(he)剩余(yu)(yu)吸(xi)(xi)(xi)(xi)附(fu)(fu)(fu)能(neng)(neng)力(li)(li)。剩余(yu)(yu)吸(xi)(xi)(xi)(xi)附(fu)(fu)(fu)能(neng)(neng)力(li)(li)是(shi)指(zhi)中(zhong)(zhong)空(kong)玻璃密封(feng)(feng)后，干(gan)燥(zao)劑(ji)吸(xi)(xi)(xi)(xi)收(shou)間(jian)(jian)隔(ge)層(ceng)(ceng)的(de)水(shui)分，使之(zhi)初始露點(dian)達到要求。除此(ci)之(zhi)外(wai)干(gan)燥(zao)劑(ji)還具有吸(xi)(xi)(xi)(xi)附(fu)(fu)(fu)能(neng)(neng)力(li)(li)，此(ci)部分吸(xi)(xi)(xi)(xi)附(fu)(fu)(fu)能(neng)(neng)力(li)(li)稱之(zhi)為剩余(yu)(yu)吸(xi)(xi)(xi)(xi)附(fu)(fu)(fu)能(neng)(neng)力(li)(li)，定量地說，它等于有效(xiao)吸(xi)(xi)(xi)(xi)附(fu)(fu)(fu)能(neng)(neng)力(li)(li)減去(qu)干(gan)燥(zao)劑(ji)吸(xi)(xi)(xi)(xi)附(fu)(fu)(fu)密封(feng)(feng)于間(jian)(jian)隔(ge)層(ceng)(ceng)內空(kong)氣中(zhong)(zhong)的(de)水(shui)分消耗的(de)吸(xi)(xi)(xi)(xi)附(fu)(fu)(fu)能(neng)(neng)力(li)(li)。剩余(yu)(yu)吸(xi)(xi)(xi)(xi)附(fu)(fu)(fu)能(neng)(neng)力(li)(li)的(de)作用是(shi)不斷(duan)地吸(xi)(xi)(xi)(xi)附(fu)(fu)(fu)從(cong)周邊(bian)擴散(san)到間(jian)(jian)隔(ge)層(ceng)(ceng)中(zhong)(zhong)的(de)水(shui)分。剩余(yu)(yu)吸(xi)(xi)(xi)(xi)附(fu)(fu)(fu)量的(de)大小(xiao)決(jue)(jue)定著對(dui)中(zhong)(zhong)空(kong)玻璃在(zai)使用過(guo)程中(zhong)(zhong)，通過(guo)擴散(san)進入間(jian)(jian)隔(ge)層(ceng)(ceng)的(de)水(shui)分吸(xi)(xi)(xi)(xi)附(fu)(fu)(fu)量的(de)大小(xiao)，也(ye)就決(jue)(jue)定著水(shui)分在(zai)間(jian)(jian)隔(ge)層(ceng)(ceng)中(zhong)(zhong)親集速率的(de)快慢，從(cong)而決(jue)(jue)定著中(zhong)(zhong)空(kong)輛的(de)有效(xiao)使用時(shi)間(jian)(jian)的(de)長短(duan)。

　　(2)減少水分通過聚合物的擴散

　　①選擇低滲透系數的密封膠

　　選擇氣(qi)(qi)(qi)體滲透(tou)系(xi)數低的(de)中(zhong)空(kong)(kong)玻(bo)璃(li)密(mi)(mi)封(feng)(feng)膠(jiao)(jiao)(jiao)(jiao)是(shi)減小(xiao)氣(qi)(qi)(qi)體擴散速率(lv)的(de)有效措(cuo)施(shi)之一(yi)。中(zhong)空(kong)(kong)玻(bo)璃(li)生產常(chang)用(yong)的(de)密(mi)(mi)封(feng)(feng)膠(jiao)(jiao)(jiao)(jiao)有丁基(ji)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)、聚(ju)硫橡(xiang)膠(jiao)(jiao)(jiao)(jiao)和(he)硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)等，其氣(qi)(qi)(qi)體滲透(tou)系(xi)數為(wei):丁基(ji)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)1~1.5g/(m2. d. cm)，聚(ju)硫橡(xiang)膠(jiao)(jiao)(jiao)(jiao)7~8g/(m2●d. cm)，硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)10~15g/(m2●d. cm)。可見，丁基(ji)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)氣(qi)(qi)(qi)體滲透(tou)系(xi)數最(zui)小(xiao)，所以雙(shuang)道(dao)密(mi)(mi)封(feng)(feng)的(de)中(zhong)空(kong)(kong)玻(bo)璃(li)由于使(shi)用(yong)了丁基(ji)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)，其有效使(shi)用(yong)期要(yao)明顯好于單道(dao)密(mi)(mi)封(feng)(feng)的(de)中(zhong)空(kong)(kong)玻(bo)璃(li)。單道(dao)密(mi)(mi)封(feng)(feng)的(de)中(zhong)空(kong)(kong)玻(bo)璃(li)(在(zai)(zai)我國逐步被(bei)淘(tao)汰)的(de)密(mi)(mi)封(feng)(feng)膠(jiao)(jiao)(jiao)(jiao)要(yao)采用(yong)聚(ju)硫膠(jiao)(jiao)(jiao)(jiao)而(er)不(bu)宜采用(yong)硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)。需(xu)要(yao)注(zhu)意(yi)的(de)是(shi)在(zai)(zai)用(yong)中(zhong)空(kong)(kong)玻(bo)璃(li)做玻(bo)璃(li)幕(mu)墻時(shi)，其雙(shuang)道(dao)密(mi)(mi)封(feng)(feng)的(de)外層(ceng)膠(jiao)(jiao)(jiao)(jiao)必須(xu)用(yong)聚(ju)硅(gui)氧烷橡(xiang)膠(jiao)(jiao)(jiao)(jiao)，因(yin)為(wei)聚(ju)硫膠(jiao)(jiao)(jiao)(jiao)和(he)幕(mu)墻施(shi)工(gong)(gong)時(shi)所用(yong)密(mi)(mi)封(feng)(feng)膠(jiao)(jiao)(jiao)(jiao)發生緩慢(man)化(hua)學反應，容易造成工(gong)(gong)程事故，應特別(bie)注(zhu)意(yi)，必要(yao)時(shi)可向有關方面咨詢。

　　②合(he)理的膠層厚度

　　由(you)式(6-6) 可以(yi)看出，氣體通過聚合物擴(kuo)散的量與(yu)膠(jiao)層(ceng)(ceng)(ceng)厚(hou)度(du)成反(fan)比(bi)。膠(jiao)層(ceng)(ceng)(ceng)越厚(hou)其(qi)擴(kuo)散量越小，所以(yi)國家標(biao)準中(zhong)規定(ding):使用雙道(dao)密封(feng)(feng)(feng)膠(jiao)時(shi)(shi)其(qi)外層(ceng)(ceng)(ceng)膠(jiao)的膠(jiao)層(ceng)(ceng)(ceng)厚(hou)度(du)為5~7mm、使用單道(dao)密封(feng)(feng)(feng)膠(jiao)時(shi)(shi)膠(jiao)層(ceng)(ceng)(ceng)厚(hou)度(du)為8~12mm,保(bao)(bao)證(zheng)(zheng)膠(jiao)層(ceng)(ceng)(ceng)厚(hou)度(du)也(ye)是減少水汽擴(kuo)散的重要(yao)一環(huan)，在生(sheng)產時(shi)(shi)一定(ding)要(yao)保(bao)(bao)證(zheng)(zheng)膠(jiao)層(ceng)(ceng)(ceng)厚(hou)度(du)和厚(hou)度(du)的均勻性。特(te)別保(bao)(bao)證(zheng)(zheng)角部密封(feng)(feng)(feng)的嚴密性。