
使(shi)用(yong)礦藏填(tian)料實現(xian)(xian)塑料的(de)填(tian)充改性,目的(de)是想在經濟上(shang)或在塑料某(mou)些功用(yong)上(shang)得到預期(qi)的(de)效果,但一同也會呈現(xian)(xian)某(mou)些不期(qi)望(wang)的(de)影(ying)響。
(1)沖擊(ji)強度
填(tian)(tian)料(liao)(liao)(liao)的(de)(de)參與往往使填(tian)(tian)充塑料(liao)(liao)(liao)抗沖(chong)(chong)(chong)擊功用(yong)下(xia)降。作為松散相的(de)(de)填(tian)(tian)料(liao)(liao)(liao)顆(ke)粒(li)(li)在(zai)基(ji)體(ti)中起到(dao)應力會集劑的(de)(de)效果,一般來(lai)說,這些(xie)填(tian)(tian)料(liao)(liao)(liao)的(de)(de)顆(ke)粒(li)(li)是剛性的(de)(de),不(bu)能(neng)在(zai)受力時(shi)變(bian)形(xing),也不(bu)能(neng)停止裂紋(wen)或發生銀紋(wen)吸收(shou)沖(chong)(chong)(chong)擊能(neng),因(yin)而會使填(tian)(tian)充塑料(liao)(liao)(liao)的(de)(de)脆性增(zeng)加。下(xia)列(lie)因(yin)素(su)有(you)(you)助(zhu)工前(qian)(qian)進沖(chong)(chong)(chong)擊強(qiang)度(du)(du):顆(ke)粒(li)(li)標準,在(zai)必定規劃能(neng)明(ming)顯前(qian)(qian)進沖(chong)(chong)(chong)擊強(qiang)度(du)(du);顆(ke)粒(li)(li)形(xing)狀,長(chang)徑比是重要因(yin)素(su),運(yun)用(yong)纖維(wei)填(tian)(tian)料(liao)(liao)(liao)是前(qian)(qian)進沖(chong)(chong)(chong)擊強(qiang)度(du)(du)有(you)(you)用(yong)的(de)(de)方法;顆(ke)粒(li)(li)硬(ying)(ying)度(du)(du),中空顆(ke)粒(li)(li)和低硬(ying)(ying)度(du)(du)的(de)(de)填(tian)(tian)料(liao)(liao)(liao)明(ming)顯下(xia)降沖(chong)(chong)(chong)擊強(qiang)度(du)(du);與基(ji)體(ti)的(de)(de)相互(hu)效果,填(tian)(tian)料(liao)(liao)(liao)表面與基(ji)體(ti)之間有(you)(you)合(he)適(shi)的(de)(de)黏合(he)(不(bu)能(neng)過強(qiang),也不(bu)能(neng)過弱)有(you)(you)助(zhu)于前(qian)(qian)進沖(chong)(chong)(chong)擊強(qiang)度(du)(du)。
近年來研(yan)討發現,選用(yong)恰(qia)當的(de)表面處理技術(shu),剛(gang)性(xing)粒(li)子(zi)相同(tong)可以(yi)達到相增韌(ren)的(de)目的(de),這便是近年展開起來的(de)剛(gang)性(xing)粒(li)子(zi)增韌(ren)理論。
(2)拉伸(shen)強度和伸(shen)長率
在填充(chong)塑猜中(zhong)重鈣(gai)粉(fen)為松散相,被分割在基體樹(shu)(shu)(shu)脂(zhi)(zhi)的(de)接連相中(zhong),在受力截(jie)面上基體樹(shu)(shu)(shu)脂(zhi)(zhi)的(de)面積必(bi)然(ran)小于純樹(shu)(shu)(shu)脂(zhi)(zhi)構成的(de)材料(liao)(liao),所以填充(chong)塑料(liao)(liao)的(de)拉(la)伸(shen)強(qiang)度較(jiao)未填充(chong)體系一般有所下降(jiang)。但(dan)假如經(jing)過(guo)表面處理(li),填料(liao)(liao)與(yu)基體樹(shu)(shu)(shu)脂(zhi)(zhi)的(de)界(jie)面黏合得好,填充(chong)體系的(de)拉(la)伸(shen)強(qiang)度或許會高(gao)于基體的(de)拉(la)伸(shen)強(qiang)度。高(gao)長(chang)徑比(bi)、高(gao)徑厚(hou)比(bi)的(de)纖維(wei)狀或片狀填料(liao)(liao)都(dou)能使復合材料(liao)(liao)的(de)拉(la)伸(shen)強(qiang)度得到(dao)改善(shan)。
關于增強型(xing)塑料,如纖維的取向和受力方向共同,且(qie)纖維表面與基體樹(shu)脂又很好(hao)的黏合,則(ze)會(hui)使填充材料的拉(la)伸(shen)強度(du)有明(ming)顯前進(jin)。
填(tian)(tian)充體系(xi)因(yin)重鈣(gai)的(de)(de)存在(zai),在(zai)遭到(dao)拉伸應力時(shi)其開(kai)裂(lie)伸長率均(jun)有(you)所(suo)下降,其首要原因(yin)是(shi)(shi)(shi)因(yin)為絕大多數填(tian)(tian)料(liao)本身(shen)是(shi)(shi)(shi)剛性的(de)(de)。但實驗研討中(zhong)發現,在(zai)填(tian)(tian)料(liao)用量低(di)于5%時(shi),而且當填(tian)(tian)料(liao)的(de)(de)粒徑又(you)是(shi)(shi)(shi)很(hen)小時(shi),填(tian)(tian)充塑料(liao)的(de)(de)開(kai)裂(lie)伸長率有(you)時(shi)比基體樹脂本身(shen)的(de)(de)開(kai)裂(lie)伸長率要高,這或許是(shi)(shi)(shi)因(yin)為在(zai)低(di)濃度(du)時(shi)填(tian)(tian)料(liao)的(de)(de)纖細顆粒與基體一同(tong)移(yi)動的(de)(de)原因(yin)。
(3)彎(wan)曲強(qiang)度
填(tian)(tian)(tian)(tian)充塑料(liao)的(de)彎曲強(qiang)(qiang)度(du)(du)(du)對大(da)多數填(tian)(tian)(tian)(tian)料(liao),都(dou)會隨填(tian)(tian)(tian)(tian)料(liao)的(de)參(can)與和份數的(de)增加(jia)下(xia)(xia)降(jiang),其下(xia)(xia)降(jiang)強(qiang)(qiang)度(du)(du)(du)與基體(ti)樹脂是(shi)否為耐性聚合(he)物以及填(tian)(tian)(tian)(tian)料(liao)的(de)幾許(xu)形狀有關,還與填(tian)(tian)(tian)(tian)料(liao)在(zai)基體(ti)中(zhong)的(de)松散狀況及加(jia)工(gong)時的(de)取向(xiang)有關。徑(jing)厚比大(da)的(de)填(tian)(tian)(tian)(tian)料(liao)或偶聯劑(ji)等(deng)表面處理劑(ji)處理的(de)填(tian)(tian)(tian)(tian)料(liao),可使耐性聚合(he)物的(de)彎曲強(qiang)(qiang)度(du)(du)(du)前進(jin)。使填(tian)(tian)(tian)(tian)料(liao)在(zai)復合(he)資猜中(zhong)取向(xiang)的(de)混合(he)方法和加(jia)工(gong)工(gong)藝,是(shi)前進(jin)填(tian)(tian)(tian)(tian)充體(ti)系彎曲強(qiang)(qiang)度(du)(du)(du)有期望的(de)途徑(jing)。
(4)彈性模量
彈(dan)(dan)(dan)性模(mo)(mo)量常(chang)常(chang)用來表征填(tian)(tian)(tian)充(chong)(chong)體(ti)系。純樹脂制(zhi)(zhi)成的(de)塑(su)料制(zhi)(zhi)品(pin)其彈(dan)(dan)(dan)性模(mo)(mo)量都比較低。重鈣(gai)粉的(de)參與使填(tian)(tian)(tian)充(chong)(chong)塑(su)料的(de)彈(dan)(dan)(dan)性模(mo)(mo)量增大(da)(da)(da),這首要是因(yin)為重鈣(gai)粉的(de)模(mo)(mo)量比聚合物的(de)模(mo)(mo)量大(da)(da)(da)許(xu)多倍。一般來說,窄分(fen)布的(de)大(da)(da)(da)顆(ke)粒填(tian)(tian)(tian)料,填(tian)(tian)(tian)充(chong)(chong)體(ti)系的(de)彈(dan)(dan)(dan)性模(mo)(mo)量的(de)增大(da)(da)(da)較少;當填(tian)(tian)(tian)料顆(ke)粒為片狀(zhuang)或纖維狀(zhuang),填(tian)(tian)(tian)充(chong)(chong)體(ti)系的(de)彈(dan)(dan)(dan)性模(mo)(mo)量明顯增大(da)(da)(da)。
此外,重鈣粉填充塑料對填料體系的緊縮強度,撕裂強度等力學性質,以及填料體系的硬度、沖突性質、熱性質、光學性質、磁電性質等其他物理性質也都會帶來必定影響。