Abubuwan da ke Shafar Zafin Canjin Gilashi, Zafin Narkewa da Zafin Guduwar Danko na Polymers

Zafin canjin gilashi (Tg), zafin narkewa (Tm) (ga polymers na lu'ulu'u) da zafin kwarara mai ƙauri (Tf) (ga polymers marasa lu'ulu'u) na polymers muhimman sigogi ne na zafin jiki. Tg yana ƙayyade zafin sabis na polymer, yayin da Tm da Tf ke ƙayyade zafin sarrafawa na polymer. Akwai abubuwa da yawa da ke tasiri ga ƙimar Tg, Tm da Tf na polymer.

Tasirin tsarin polymer da kaddarorinsa

I. Tsarin sarka

(1) Babban sarka. Gabatar da ƙungiyoyi masu tauri kamar phenyl, biphenyl groups da haɗin gwiwa biyu a kan babban sarka yana ƙara tauri na sarka, yayin da Tg, Tm da Tf duk suna ƙaruwa; shigar da haɗin ether da haɗin gwiwa biyu da aka ware a kan babban sarka yana sa sarka ta zama mai sassauƙa, kuma Tg, Tm da Tf duk suna raguwa.

(2) Ƙungiyoyin Gefen. Idan ƙungiyar gefe ƙungiya ce mai tauri, sassaucin sarkar yana raguwa yayin da ƙarar ƙungiyar gefe ke ƙaruwa, kuma Tg, Tm da Tf duk suna ƙaruwa; lokacin da ƙungiyar gefe (ko sarkar gefe) ƙungiya ce mai sassauƙa (ko sarkar sassauƙa), girman ƙungiyar gefe (sarkar), mafi kyawun sassauci, to sassaucin sarkar kwayoyin halitta ya fi kyau, kuma Tg, Tm da Tf duk suna raguwa.

Haɗin (1) da (2) ya nuna cewa duk abubuwan da ke ƙara taurin sarka na iya ƙara ƙimar Tg, Tm da Tf, kuma duk abubuwan da ke ƙara sassaucin sarka na iya rage ƙimar Tg, Tm da Tf.

II. Ƙarfin da ke tsakanin ƙwayoyin halitta
Polymers na polar, tare da hulɗa mai ƙarfi tsakanin ƙungiyoyin polar akan sarkar kwayoyin halitta da ƙarfin intermolecular mai ƙarfi, suna da ƙimar Tg, Tm da Tf mafi girma fiye da ƙimar da ta dace da polymers marasa polar; kuma ƙimar Tg, Tm da Tf duk suna ƙaruwa tare da ƙaruwar ƙarfin intermolecular.

III. Nauyin kwayoyin halitta
Ganin cewa Tm yana da alaƙa da lu'ulu'u, gabaɗaya, nauyin kwayoyin halitta ba shi da wani tasiri a kan Tm kuma duka Tg da Tf suna ƙaruwa tare da ƙaruwar nauyin kwayoyin halitta. Ga Tg, wannan yanayin ya fi bayyana a ƙananan nauyin kwayoyin halitta, yayin da Tg ke canzawa a hankali lokacin da nauyin kwayoyin halitta ya ƙaru zuwa wani mataki.

Tasirin nauyin kwayoyin halitta akan Tf ya fi muhimmanci fiye da na Tg. Wannan saboda tasirin nauyin kwayoyin halitta akan Tg ana danganta shi da tasirin ƙarshen sarkar, wanda za'a iya nunawa ne kawai lokacin da abun da ke cikin ƙarshen sarkar tsarin ya yi yawa, watau nauyin kwayoyin halitta ya yi ƙasa kaɗan; bayan nauyin kwayoyin halitta ya yi yawa zuwa wani matsayi kuma nauyin ƙarshen sarkar ya yi ƙanƙanta zuwa wani matsayi kaɗan, tasirinsa akan Tg ba shi da mahimmanci.

Tf shine zafin jiki mai mahimmanci wanda tsakiyar nauyin dukkan sarkar polymer ke motsawa, kuma motsi na dukkan sarkar yana samuwa ta hanyar motsi mai haɗin gwiwa na dukkan sassan sarkar. Mafi girman nauyin kwayoyin halitta, mafi girman adadin sassan sarkar da ke buƙatar motsawa tare, kuma mafi girman ƙarfin gogayya da ke buƙatar shawo kan su yayin motsi, kuma mafi girman Tf. Saboda haka ƙimar Tf ta dogara sosai akan nauyin kwayoyin halitta.

Tasirin abubuwan waje

I. Ƙananan ƙarin ƙwayoyin da ke narkewa

A wasu lokutan ana ƙara plasticizers ko wasu ƙarin abubuwa masu narkewa a cikin sinadaran don inganta halayen sarrafawa ko kuma don ba da wani ɓangare ga samfurin yayinSamar da polymer da sarrafawaA yanayin polymers, waɗannan ƙananan ƙwayoyin suna daidai da masu narkewa kuma suna rage Tg, Tm da Tf na polymer.

II. Ƙarfin waje

Ƙarfin waje mai sassauƙa yana da tasirin turawa akan sassan sarka, don haka ƙara ƙarfin waje na iya rage Tg da Tf. Ƙara tsawon lokacin ƙarfin waje kuma yana fifita motsin ƙwayoyin halitta a cikin alkiblar ƙarfin waje, wanda kuma yana rage Tf. Ƙara matsin lamba yana rage girman 'yanci kuma yana ƙara Tg da Tf.

Tasirin ƙarfin waje akan Tm kamar haka: lokacin da polymer ya yi lu'ulu'u a ƙarƙashin ƙarfin tauri, ikon lu'ulu'u yana ƙaruwa, yana haɓaka matakin lu'ulu'u da kuma wurin narkewar lu'ulu'u, watau Tm yana ƙaruwa; lu'ulu'u a ƙarƙashin matsin lamba yana ƙara kauri na wafer, wanda ke ƙara kamalar lu'ulu'u, yana kuma sa Tm ya fi girma.

III. Yawan gwaji

Wannan yana cikin girman ƙimar gwajin da aka samu dangane da gwajin zafin jiki. Tunda motsi na sarƙoƙin polymer tsari ne na shakatawa kuma ya dogara da lokaci, akwai alaƙa tsakanin ƙimar gwajin Tg da sikelin lokacin gwaji: ƙara yawan ɗumamawa ko yawan gwaje-gwaje masu ƙarfi zai ƙara Tg. Haka yake ga Tf, kuma akasin haka yake ga Tm. Lokacin gwada ƙimar Tm, idan an ƙara zafin a hankali, ana iya narke hatsi marasa cikawa da farko sannan a sake sake haɗa su zuwa lu'ulu'u mafi kyau da kwanciyar hankali a ƙaramin zafin jiki. Abin da ake kira "wurin narkewa" na ƙarshe shine zafin jiki wanda duk lu'ulu'u mafi cikakke ke narkewa kuma zai fi ƙimar da aka auna a cikin hawan zafin jiki mai sauri.