Thaum tshawb nrhiav cov yam ntxwv ntawmkub yaj adhesivesNyob rau hauv ib puag ncig uas tsis tshua muaj kub, "embrittlement" yog qhov teeb meem tseem ceeb. Feem ntau, kub - yaj nplaum nplaum yuav ua nkig vim qhov kub thiab txias.
Kub - yaj nplaum nplaum yog tsim los ntawm polymers, tackifiers, waxes, thiab lwm yam khoom. Nyob rau hauv ib puag ncig uas tsis muaj qhov kub thiab txias, kev txav mus los ntawm cov saw hlau polymer molecular tau txo qis, thiab kev txav ntawm cov saw ntu yuav nyuaj. Qhov no ua rau muaj qhov txo qis hauv qhov qub yooj thiab elasticity ntawm cov nplaum nplaum kub-kub, thiab qhov tseem ceeb nce hauv brittleness.
Siv EVA kub - yaj nplaum ua piv txwv. Thaum lub ambient kub poob qis dua 0 degree, nws hardness nce sai, thiab nws yooj yim txo. Thaum lub caij ntuj no nyob rau sab qaum teb, yog tias cov khoom sib txuas nrog EVA kub - yaj nplaum tau muab tso rau sab nraum zoov, cuam tshuam los ntawm qhov kub thiab txias, cov nplaum nplaum kub yog qhov ua rau tawg, ua rau tsis ua haujlwm ntawm cov khoom sib txuas.
Txawm li cas los xij, tsis yog tag nrhokub yaj adhesivesNws yog heev yooj yim mus embrittlement ntawm tsawg kub. Los ntawm kev tsim tshwj xeeb thiab kev hloov kho, qee qhov kub-kub nplaum nplaum tuaj yeem tswj tau qhov yooj yim ntawm qhov kub thiab txias. Piv txwv li, ntxiv cov yas tshwj xeeb lossis elastomers rau cov kua nplaum kub yaj tuaj yeem txhim kho nws qhov kev ua haujlwm kub. Siab - rhiab kub - yaj nplaum nplaum, vim lawv cov qauv molecular tshwj xeeb, tseem tuaj yeem tswj tau qee qhov elasticity thiab yooj ntawm qhov kub thiab txias, ua rau lawv tsim nyog rau cov xwm txheej uas yuav tsum tau ua rau qhov kub thiab txias.