Yuav Ua Li Cas Txhim Kho Qhov Tsawg -Tsub Ua Haujlwm Ntawm Cov Khoom Roj Hmab?

Tawm tsam keeb kwm yav dhau los ntawm cov xwm txheej huab cua ntau zuj zus thiab puas tau -cov khoom lag luam nyuaj ua haujlwm ntau dua, kev ua haujlwm ntawm cov khoom siv roj hmab hauv qab - qhov kub thiab txias tau dhau los ua qhov taw qhia tseem ceeb rau kev ntsuas lawv cov nqi thov tag nrho. Txawm hais tias nyob rau hauv lub tsheb foob, cov roj cryogenic foob, cov khoom siv tshawb nrhiav lub ncov qaumteb qabteb, aerospace piping, cable sheathing, los yog tub rog Cheebtsam, qis - kub tsis kam cuam tshuam ncaj qha rau kev pab cuam lub neej thiab kev ntseeg siab.

Daim ntawv no qhia txog qhov qis - tus cwj pwm kub ntawm cov khoom siv roj hmab tam sim no, cov tswv yim xaiv cov khoom siv, plasticization thiab crosslinking tswj, kev tsim kho kom zoo, nrog rau cov lus pom zoo thiab cov ntaub ntawv siv. Nws pab cov kws kho mob hauv kev paub txog kev hloov kho cov khoom siv roj hmab ua haujlwm ntawm qhov kub ntawm -40℃thiab qis dua.

NBR Rubber Sealing Ring

I. Ua tsis tiav Mechanisms ntawm cov khoom siv roj hmab hauv Cryogenic ib puag ncig

Roj hmab ntsib ob qho kev sib tw ua haujlwm tseem ceeb ntawm qhov kub thiab txias:

1. Kev hloov iav (Tg):Thaum ambient kub poob qis dua cov roj hmab lub iav hloov pauv kub (Tg), cov khoom hloov los ntawm lub xeev siab heev mus rau lub xeev iav. Qhov no manifests raws li ib tug tseem ceeb nce nyob rau hauv rigidity thiab ib tug cim txo nyob rau hauv yooj, muaj peev xwm culminating nyob rau hauv brittle fracture.

2. Crystallisation tus cwj pwm:Qee cov roj hmab (piv txwv li, NR, CR) pom cov crystallisation ntawm qhov kub thiab txias, ua rau cov khoom tawv tawv thiab txawm tias micro- tawg.

Yog li ntawd, tus yuam sij rau kev tsim qis -kub- cov tshuaj tiv thaiv yog nyob rau hauv txo Tg thiab txo qis -kub crystallisation tus cwj pwm.

II. Cov ntsiab lus tseem ceeb ntawm Kev Xaiv Cov Khoom Siv: Tg yog qhov kev txiav txim siab tseem ceeb

Cov lus hauv qab no nthuav tawm cov iav hloov pauv kub (Tg) rau cov roj hmab sib xws, tau los ntawm cov ntaub ntawv sau ua ke xws li Rubber Technology Phau Ntawv Qhia:

Hom roj hmab	Tg (degree)
MVQ (Vinyl Silicone Roj Hmab)	-120
BR (butadiene roj hmab)	-112
NR / IR (Natural / Isoprene Rubber)	-72
FVMQ (fluorosilicone roj hmab)	-70
IIR (Butyl Rubber) thiab Nws Cov Ntawv Hloov Kho	-66
PNF (Polyfluorophosphazene)	-66
EPDM (Ethylene Propylene Diene Monomer Roj Hmab)	-55
SBR (styrene -butadiene roj hmab)	-50
NBR (Low ACN)	-45
NBR (Low ACN)	-45
ACM (acrylic acid ester)	-40~-20
FKM (fluoroelastomer)	-50~-18
PNR (Poly{0}}norbornene)	+25

Pom zoo qis-Tg cov khoom sib txuas: MVQ, BR, FVMQ, IIR, qis-ACN NBR

III. Kev tiv thaiv tus cwj pwm crystallisation: Kev sib xyaw cov txheej txheem polymer thiab cov tswv yim sib xyaw

1. Kev pheej hmoo thiab kev tiv thaiv rau cov roj hmab crystalline

Yog tsis tsim nyog compounding lossis plasticisation ntawm qhov kub thiab txias, cov ntaub ntawv xws li NR thiab CR tuaj yeem crystallise, ua rau kev ua haujlwm tsis zoo.

Pom zoo tiv thaiv:

NR/BR blending: BR's non{0}}crystalline xwm zoo cuam tshuam NR's crystallisation sequence, txhim kho zuag qhia tag nrho yooj;

Tswjhwm crosslink ntom ntom: Ib nrab txo qhov crosslinking℃nce ntu txav, qeeb crystallisation tus nqi.

2. Silicone Rubber Crystallisation Countermeasures

Txheem VMQ crystallises hauv qab -45 degree. Qhia 5-7 mol% phenyl pawg thaum lub sij hawm polymerisation tsim ib tug PVMQ qauv, zoo inhibiting crystallisation thiab ncua daim ntawv thov txo qis rau -90 degree.

EPDM Rubber O-Ring

IV. Kev Xaiv Plasticiser: Qhov Kev Txiav Txim ntawm Flexibility

Qhov ua tau zoo tsawg-kub plasticiser yuav tsum txaus siab: tsis muaj viscosity, tsis hloov pauv, siab sib xws, Tg tsawg, thiab tsis muaj kev tsiv teb tsaws. Hom kev pom zoo yog raws li nram no:

Hom	Piv txwv	Siv tau cov neeg tuaj saib	Yam ntxwv
Esters	DOA (dioctyl adipate), DMBTG, DBEEA	NBR, HNBR	Zoo thermal stability, tsawg Tg
Tshwj xeeb ester	C7C11P	NBR Hloov kho	Tej zaum zoo dua DOA
LPPM (Low Polar Polyesters)	Polyester	NR/EPDM/SBR	Txhim khu kev yooj yim, tsis muaj kev pheej hmoo los nag
Butyl hmoov	CR hloov kho	Tus nqi qis, kev ua haujlwm siab

Cov lus ceeb toom tshwj xeeb: Tsawg-molecular- hnyav ester monomers feem ntau ua tau zoo tshaj -viscosity polymeric plasticisers, nrog tsawg tsawg txaus los txhim kho NR qis- kev ua haujlwm kub.

V. Tsawg-Tsuas Tsim rau Thermoplastic Elastomers

TPV (piv txwv li, EPDM/PP): Hloov mus rau qis-ethylene, qis-crystallinity EPDM matrices ncua lawv qhov qis- kub txwv;

TPU: Xaiv cov ether- hom qauv nrog MDI raws li cov khoom siv prepolymer, uas nthuav tawm Tg qis dua thiab tsim nyog rau cov cables thiab cov khoom sib khi hauv qhov chaw txias.

VI. Cov ntsiab lus tseem ceeb rau qis-Tsub Optimization ntawm Ntau Cov Roj Hmab Tshwj Xeeb

Khoom siv	Tsawg-tej qauv tsim qauv kub
EPDM	Xaiv cov qib amorphous nrog cov ntsiab lus ethylene tsawg; siv metallocene-catalysed EPDM thev naus laus zis los kho cov ntsiab lus melting faib thiab tiv thaiv crystallisation; nce cov ntsiab lus copolymerized diene kuj tau txais txiaj ntsig.
NBR	Xaiv cov qib qis ACN (acrylonitrile) cov ntsiab lus tuaj yeem txo Tg zoo thiab txhim kho yooj
HNBR	Siv LT-HNBR qib: qis ACN. Qhov thib peb comonomer (mos qauv, ntim loj) inhibits crystallisation.
FKM	Hloov mus rau PMVE es tsis txhob HFP los txhim kho qis - qhov kub thiab txias; Feem ntau, zoo li Viton GLT / GFLT series
SBR	Xaiv cov qib uas muaj cov ntsiab lus styrene tsawg
CSM/CPE	Xaiv cov khoom uas muaj cov tshuaj chlorine tsawg

VII. Kev Tswj Xyuas Kev Pom Zoo

1. Tswj Crosslink ceev

Whilst high crosslink density txhim kho cov khoom siv kho tshuab, nws cuam tshuam qis -kub yooj yim. Cov ntsiab lus sulfur thiab accelerator ratios nyob rau hauv lub vulcanization system yuav tsum tau tswj kom tsim nyog.

2. Co-Agent Optimization

Piv txwv li, qhia Ricon®- hom kua siab -vinyl polybutadiene co- cov neeg ua haujlwm rau hauv EPDM peroxide vulcanisation systems outperforms ib txwm TMPTMA co- cov neeg ua haujlwm, xa cov kev ua haujlwm qis tshaj - kub.

VIII. Cov ntaub ntawv siv tau

Daim ntawv thov scenario	Kev pom zoo System	TG Improvement Plan
Extreme txias cheeb tsam tsheb sealing sawb	EPDM + LPM	Tswj cov ntsiab lus ethylene, Polyester plasticisers
-40℃roj foob	CR + DOA/Butyl Oleate	Tswj crosslinking softener
Tub rog foob	HNBR + DBEEA	Tsawg ACN hloov tau thib peb monomer
Ultra-tsawg kub aviation pipeline	PVMQ	Qhia phenyl los inhibit crystallisation

IX. Cov ntsiab lus xaus: Kev xav hauv lub cev rau lub tsev ruaj khov qis-Kev ua haujlwm kub

Tsawg- qhov kub thiab txias tsis tuaj yeem ua tiav los ntawm kev cia siab rau ib qho khoom siv lossis ntxiv ib leeg. Nws yog kev sib koom ua ke ntawm kev xaiv cov roj hmab hauv paus + muab tub lim sib txuam + plasticising system + crosslinking qauv + txheej txheem qhov rai. Cov kws kho mob tau qhia kom ua raws li cov hauv paus ntsiab lus no thaum lub sij hawm tsim qauv tsim:

Txhais qhov kev khiav hauj lwm qhov kub thiab txias, nrog Tg kwv yees raws li qhov pib taw tes;

Ua ke nrog kev ntsuas qhov tseeb, xws li TR-10, DSC, thiab DMA tsom xam rau kev siv tau;

Kev ntsuas ntsuas qis-kub tus cwj pwm nyob rau hauv crosslinking, kev ua, hnub nyoog, thiab roj- nruab nrab tej yam kev mob;

Ua cov qauv sib txuas- mus rau- khoom siv tau, teeb tsa theem qis- qhov ntsuas kub tsis kam.