Dab tsi ua rau cov roj av ntsaws ruaj ruaj?
Ua cov khoom siv hluav taws xob zoo nkauj, roj hmab yuav nyuaj thaum lub sijhawm nws siv, ua rau muaj kev txo qis hauv lub neej ntawm cov khoom. Muaj ntau ntau cov laj thawj yog vim li cas roj hmab ntsaws ruaj ruaj, suav nrog lub cev, tshuaj lom neeg, thiab thev naus laus zis ib puag ncig. Cov hauv qab no yuav yog qhov kev ntsuas muaj ntau yam xws li kev sib txuas lus sib txawv, cov mis cuam tshuam, cov txheej txheem ib puag ncig, thiab kev siv thev naus laus zis.
Lub tshuab ntawm cov tawv ntoo ntawm cov roj hmab ntsaws ruaj ruaj
Cov laj thawj tseem ceeb rau kev nce hauv lub hardness ntawm roj hmab ntsaws ruaj ruaj suav nrog:
1. Nce degree ntawm cross-sib txuas - Vulcanization txuas ntxiv nce, uas txwv kev txav ntawm cov roj hmab saw ntu thiab tawv tawv cov khoom siv.
2. Poob ntawm cov yas dawb - lub tsiv teb tsaws lossis tsis loj ntawm cov roj av qis xws li cov tshuab yas thiab cov muag khoom ua kom cov roj hmab poob nws txoj kev yooj yim.
3. Molecular chain degradation - lub ntsiab ntawm cov roj hmab molecules tau tawg, ua rau muaj kev puas tsuaj rau cov qauv network loj, uas yog qhov hloov pauv ntawm Hardness.
4. Tus muab kev sib cav sib cais lossis theem sib cais - fillers (piv txwv li, carbon dub, silica) sib sau lossis khom hauv cov roj hmab loj, ua kom muaj zog hauv zos.
Lub ntsiab tseem ceeb ntawm lub stiffening ntawm roj hmab ntsaws ruaj ruaj
Kev hloov pauv ntawm kev sib txuas-txuas qauv
Cov qib ntawm vulcanization crosslinking roj hmab muaj cov nyhuv tseem ceeb ntawm nws lub hardness:
· Operations: Lub sijhawm ua kom tsis muaj zog lossis qhov kub tau siab dhau lawm, ua rau cov roj hmab ua kom nyuaj, ua rau cov roj hmab ua kom nyuaj, thiab poob nws qhov yooj.
Elcarhaly vulcanization (tom qab rov kho dua) nyob rau hauv kev sib txuas ntawm cov roj hmab uas muaj kev sib txuas lus hnyav thiab cov tshuaj fluorone yuav ua rau muaj kev sib txuas lus hnyav thiab cov tshuaj fluoring.
· Tus neeg sawv cev ua rau muaj kev lim hiam ntev ntev, xws li cov neeg ua haujlwm sib txawv, thiab cov khoom siv hluav taws xob ntau dhau) yuav ua rau cov roj hmab sib txuas.
· Vulcanization tshuab (xws li kev sib tw Monosulfide, thiab cov sib txawv ntawm cov kev sib txuas ntawm cov roj hmab, thiab cov ntawv disulffide thiab monosulfide daim ntawv cog lus thiab monosulfide bonds yog qhov nyuaj dua li cov pob zeb polysulfide.
Kev Laus Mechanism
Kev laus yog ib qho kev ua kom tawv tawv ntawm cov roj hmab ntsaws ruaj ruaj, thiab cov kev laus laus yam suav nrog:
(1) thermal-oxidative laus
· Qhov kub siab yuav txhawb nqa oxygen li cas, ua rau lub ntsej muag molecules, ua rau lub zog ntawm cov roj hmab foob.
· Raug thermal-oxidative Cov Neeg Laus Cov Lus Qhia: R-H + O2 → R-O2 → R-O2 → R-Oxidation Oxidating Linking thiab hardens lub tshuab roj hmab.
(2) Ozone Aging
· Ozone tuaj yeem rhuav tshem ob daim ntawv sib tw tsis tau muaj sia, ua rau nws tsim oxidative-txuas thiab txhim kho hardness. Piv txwv li, roj hmab nrog ob chav sib khi, xws li NR, SBR, Br, thiab lwm yam.
(3) ultraviolet laus
UV hluav taws xob ua rau muaj kev hloov pauv dawb uas nrawm oxidating oxiding hla kev sib txuas thiab ua kom cov roj hmab ua kom tawv roj hmab. Tshwj xeeb, roj hmab cov khoom siv sab nraud, xws li cov ntsaws ruaj ruaj thiab cov log tsheb, yuav ua nyuaj thiab nkig thaum lub hnub ci rau lub hnub ntev.
(4) hydrolytic laus
· Roj hmab Roj Hmab Muaj cov pab pawg Ester (-Coo-
(5) Kev laus hluav taws xob
Kev siv hluav taws xob siab xws li hluav taws xob nuclear thiab xoo hluav taws xob tuaj yeem ua rau tawg lossis hla kev sib txuas roj hmab molecular, yog li hloov lawv lub hardness. Piv txwv li, cov roj hmab khoom hauv aerospace thiab nuclear kev lag luam yuav tsum tau txiav txim siab tshwj xeeb rau kev tiv thaiv hluavtaws hluav taws xob.
Tsim Kom Zoo
Cov khoom sib txawv ntawm cov roj hmab tsim muaj qhov cuam tshuam tseem ceeb rau kev hloov pauv nyuaj:
Cov nyhuv ntawm fillers
· Roj av dub carbon dub (piv txwv li, n220, n330) tuaj yeem nce hardness, thaum tus nqi qis carbon dub (piv txwv li, N660) tau ua haujlwm tsawg dua.
Tam sim no muab cov ntsaws ruaj khov, tshwj xeeb yuav ua rau cov roj hmab nyuaj, tshwj xeeb tshaj yog cov pab pawg neeg hydroxyl hauv qab huab cua.
· Inoracanic fillers xws li calcium carbonate, talc, av nplaum, thiab lwm yam yuav ua rau cov roj hmab rigidity thiab nce lub hardness.
Cov nyhuv ntawm cov tshuab yas / muag khoom
· Cov tshuab hluav taws xob vov loj los yog tsiv teb chaws xws li roj paraffin, dop (doctyl), uas yuav tsiv teb chaws lossis siv roj hmab kom poob nws cov muag muag thiab ua nyuaj.
Eprade esteners abrade ester cov yas roj uas decompose nyob rau hauv kev kub siab lossis hydrolytic mob, hardening roj hmab.
Qhov cuam tshuam ntawm antioxidants
· Eh estexidant hom xws li TMQ, 6PPD, thiab lwm yam. Muaj peev xwm ncua sij hawm thermal thiab oxidative kev laus thiab tiv thaiv cov roj hmab los ntawm cov tawv nqaij tawv.
· EantoloXidant Kev Siv Sij Hawm Ntev, cov antioxidant yog maj depleted, thiab cov laus tus nqi accelerates, ua kom muaj zog.
Qhov cuam tshuam ntawm cov kab ke hla kev sib txuas
· Vurcurcanization xaiv
Lub cev muaj peroxide vulcanization system yog qhov nyuaj dua li cov sulpur vulcanization system;
Lub cob qhia kev ua kom muaj kuab paug yog qhov yooj yim los ua rau cov roj hmab kom tawv;
Kev siv ntawm vulcanized system nrog kev sib txuas siab hla kev sib txuas yuav nrawm ua kom tawv tawv.
· Accelerator noj tshuaj tiv thaiv
Cov roj nrawm dhau yuav ua rau muaj kev ua kom huv, ua kom tawv tawv ntawm cov roj hmab;
Kev ua kom nrawm nrawm yuav ua rau tsis txaus vulcanization thiab tsis muaj zog tab sis kuj yuav kis tau txuas ntxiv mus txuas ntxiv thiab tawv tom qab.
Environmentalency
Thaum muaj kev cuam tshuam nrog cov pa roj hmab hloov chaw nyob qis qis, xws li muaj kev sib tsoo ntawm NR thiab SBR thaum tsis kub.
· Kev vam meej rau cov kev siv hydrolysis lossis hla kev sib txuas ntawm qee yam rubbers, yog li ntawd lub zog ua kom muaj zog.
Tshuaj lom neeg sib cuag nrog cov tshuaj lom neeg, roj, cov kuab tshuaj, yuav ua rau cov qauv hloov roj ntawm cov roj hmab, nce nws lub hardness.
Cov Txuj Ci
Teb sib xyaw ua ke ntawm cov puv tsev thiab cov neeg sawv cev uas muaj kev sib xyaw ua ke yuav ua rau tsis muaj kev sib txuas ntawm cov chaw ib cheeb tsam, uas tau ua rau muaj kev nyuaj siab tsis meej.
Poj ntsuam lub sij hawm tswj cov sij hawm ua kom tsis pub siv lub sijhawm ntev dhau yuav ua rau muaj kev nyuaj ntawm cov roj hmab.
· Tsis muaj qhov chaw cia khoom kub kom kub, oxygen, thiab ozone rau lub sijhawm ntev yuav ua rau kev sib txuas lossis kev laus ntawm cov roj hmab, ua rau txhav tawv.