大家好,我是小編。今天給大家介紹永久性防(fang)靜電(dian)母(mu)粒,以下內容由小編整理,相關內容供以參考。
永久性(xing)防靜電(dian)母粒作用機理的(de)雙向拉伸聚(ju)丙烯(BOPP)薄(bo)膜(mo)是聚(ju)丙烯專有料添(tian)加適當的(de)功能助劑后(hou)經過(guo)雙向拉伸工藝后(hou)得到的(de)一種結晶型產(chan)品。
由于(yu)聚(ju)丙烯(xi)為典型的非(fei)極性高分子(zi)材料,吸水性極差(cha),當受到(dao)(dao)(dao)摩擦后表(biao)面(mian)產(chan)生的電(dian)(dian)(dian)(dian)(dian)荷(he)很難(nan)散去(qu),使(shi)之靜(jing)電(dian)(dian)(dian)(dian)(dian)性很強。為了消除在膜(mo)表(biao)面(mian)產(chan)生的電(dian)(dian)(dian)(dian)(dian)荷(he)需要加(jia)入抗靜(jing)電(dian)(dian)(dian)(dian)(dian)劑(ji)。抗靜(jing)電(dian)(dian)(dian)(dian)(dian)母粒是(shi)一種雙極性物質,它(ta)能遷(qian)移(yi)到(dao)(dao)(dao)薄膜(mo)表(biao)面(mian),吸收空氣中的水分,形(xing)成導電(dian)(dian)(dian)(dian)(dian)層,及(ji)(ji)時(shi)散去(qu)積(ji)聚(ju)的電(dian)(dian)(dian)(dian)(dian)荷(he),使(shi)之具有控(kong)制(zhi)帶電(dian)(dian)(dian)(dian)(dian)的能力。這種疏散電(dian)(dian)(dian)(dian)(dian)荷(he)的能力對于(yu)聚(ju)丙烯(xi)薄膜(mo)的加(jia)工及(ji)(ji)使(shi)用是(shi)非(fei)常必(bi)要的。否則在生產(chan)過程中,由于(yu)靜(jing)電(dian)(dian)(dian)(dian)(dian)會使(shi)操作人員受到(dao)(dao)(dao)電(dian)(dian)(dian)(dian)(dian)擊;在制(zhi)袋或包(bao)裝商品(pin)時(shi),表(biao)面(mian)電(dian)(dian)(dian)(dian)(dian)荷(he)會使(shi)薄膜(mo)粘附在包(bao)裝設(she)備上;對于(yu)包(bao)裝后的商品(pin),由于(yu)靜(jing)電(dian)(dian)(dian)(dian)(dian)現象,在存(cun)放或者銷售過程中會吸附灰塵,影響產(chan)品(pin)的形(xing)象。
永久性防靜電(dian)(dian)母(mu)粒靜電(dian)(dian)消除的能力是以(yi)BOPP薄(bo)膜表(biao)面(mian)積(ji)聚(ju)的電(dian)(dian)荷衰減到一半(ban)值(zhi)所表(biao)示的時間,即靜電(dian)(dian)半(ban)衰期值(zhi)來衡量(liang)。
抗(kang)靜電劑(ji)具有遷移(yi)性,抗(kang)靜電劑(ji)加入(ru)聚合(he)物后,它會(hui)從加入(ru)層(ceng)遷移(yi)到(dao)含量小或未加入(ru)層(ceng)。因(yin)(yin)此,在實際生產(chan)過(guo)程(cheng)中,一(yi)般只把它加到(dao)薄膜的芯層(ceng)材料中。否則,如果(guo)把抗(kang)靜電劑(ji)加到(dao)表(biao)層(ceng),它就會(hui)因(yin)(yin)反向遷移(yi)往芯層(ceng)而(er)消耗掉,起(qi)不到(dao)抗(kang)靜電的作用。
永(yong)久性防靜電(dian)母(mu)粒(li)加入芯(xin)層的(de)抗靜電(dian)劑的(de)遷移(yi)能(neng)力,受存放溫度(du)和存放時間的(de)影(ying)響。在允許范圍內,溫度(du)越高遷移(yi)速度(du)越快。在相同溫度(du)下,遷移(yi)要有一(yi)個過(guo)程,一(yi)般(ban)要存放一(yi)到兩周。此外,抗靜電(dian)母(mu)粒(li)作用機理聚合(he)物的(de)結晶(jing)度(du)對添加劑的(de)遷移(yi)程度(du)也(ye)有明顯的(de)影(ying)響。