Mfomso a ɛda nsow a ɛwɔ fluoroelastomer (FKM) so ne ɔhyew a ɛba fam a entumi nnyina ano yiye. Ɔhyew a ɛba fam a ɛtwetwe (TR10) a ɛwɔ binary FKM mu no taa yɛ -18 kosi -16 °C, na ahwehwɛ nsakrae hyew (Tg) yɛ -20 °C; ɔhyew a ɛba fam a ɛko tia FKM abiɛsa no nyɛ papa sen nea ɛwɔ FKM abien no mu. Special low-temperature type FKM wɔ low-temperature resistance pa, nanso ne bo yɛ den yiye.
FKM wɔ ASTM D 2000-2012 'automotive rubber products standard classification system' a ɛwɔ M2, M5, M6 grade nneɛma a ɛhia sɛ wɔtwam wɔ low-teature embrittlement F15 (-25 °C) sɔhwɛ mu, M4 grade nneɛma a ɛhia sɛ wɔtwa low-temperature embrittlement F17 (-40 °C) sɔhwɛ no mu. Wɔ nnansa yi mfe mu no, wɔhwehwɛ sɛ FKM nneɛma pii na ama wɔadi ahwehwɛde ahorow a ɛfa ɔhyew a ɛkɔ soro a ɛko tia (250-275 °C) ne ɔhyew a ɛba fam a ɛyɛ mmerɛw F15 anaa F17 nyinaa ho dwuma. Ɔkwan pa ne sɛ wode FKM a ɛyɛ hyew a ɛba fam bedi dwuma, te sɛ brittleness temperature a ɛyɛ -45 ~ -40 °C Viton GLT type FKM, nanso saa FKM ɔhyew a ɛkorɔn yi adwumayɛ nyɛ papa na ɛyɛ den sɛ wɔbɛma ne bo ayɛ nea wogye tom wɔ gua so. Ɛdenam adwumayɛ a ɛkɔ anim so no, FKM nnuru abien betumi adi ahwehwɛde ahorow a ɛfa ɔhyew a ɛba fam ne nea ɛkɔ soro ho dwuma bere koro mu, na ɛka a wɔbɔ nso yɛ nea ntease wom, abɛyɛ beae a wɔyɛ nhwehwɛmu a ɛyɛ hyew.
Saa krataa yi hwehwɛ FKM low-temperature performance of Tg, TR10 ne brittleness temperature (Tbri) abusuabɔ a ɛda postgraduate asuafo, fillers, mixing process, ne nea ɛkeka ho ntam wɔ binary ne ternary FKM adhesive low-temperature brittleness adwumayɛ so ma ahosiesie a ɛba fam-temperature-resistant FKM adhesive de ma nkyerɛkyerɛmu!
1. FKM a ɛyɛ hyew a ɛba fam embrittlement su ahorow no su
Rɔba wɔ deformation a wotumi dannan mu, ebetumi ama deformation kɛse aba wɔ abɔnten tumi ketewaa bi dwumadi ase, na wobetumi asan de ne mfitiase tebea no aba bere a wɔayi abɔnten tumi no afi hɔ akyi, enti wɔde di dwuma kɛse. Nanso bere a ɔhyew no so tew no, rɔba no ahoɔden a ɛyɛ den no sɛe nkakrankakra, na sɛ edu Tg a, rɔba no hwere nea ɛyɛ den no na entumi nyɛ adwuma yiye. Esiane sɛ rɔba nneɛma ahorow nti, wɔ ɔkwan a wɔfa so de di dwuma no mu no wobetumi ayɛ nea wɔde bɛbɔ, nhyɛso, twitwa, torsion, extrusion, abrasion, ne nea ɛkeka ho, ɛsɛ sɛ ne low-temperature embrittlement adwumayɛ gyina n’adwuma tebea so de paw sɔhwɛ kwan a ɛfata. Akwan a wɔtaa de di dwuma wɔ ɔhyew a ɛba fam embrittlement adwumayɛ sɔhwɛ akwan no bi ne Tg sɔhwɛ, nkɛntɛnso brittleness ɔhyew sɔhwɛ, ɔhyew a ɛba fam retraction sɔhwɛ, ɔhyew a ɛba fam torsional rigidity sɔhwɛ (Gimen sɔhwɛ), resistance to stretching ne awɔw coefficient sɔhwɛ, low-ɔhyew hardness sɔhwɛ, low-ɔhyew compression daa deformation ne stress relaxation sɔhwɛ, ne nea ɛkeka ho.
FKM no ɔhyew a ɛba fam a ɛko tia no betumi ayɛ nea Tg, Tbri, TR10 ne Torsion Temperature at low temperature (TGem), ne nea ɛkeka ho Saa nsusuwii ahorow yi wɔ ntease ahorow nanso ɛwɔ abusuabɔ bi ne wɔn ho wɔn ho.
(1) Tg yɛ ɔhyew a rɔba no sesa fi tebea a ɛyɛ den kɛse mu kɔ tebea a ɛyɛ ahwehwɛ mu ne tebea a ɛte sɛ ahwehwɛ no kɔ tebea a ɛyɛ den kɛse mu, a ɛtaa kyerɛ sɛnea rɔba molecule nkɔnsɔnkɔnsɔn no kɔ baabiara a ɛyɛ ketewaa.
(2) Tbri yɛ ɔhyew a biribiara nsɛe rɔba no wɔ tebea horow a wɔakyerɛ a ɛfa tumi a ɛde ba no mu, a ɛtaa kyerɛ ahoɔden a rɔba no wɔ sɛ wɔde bedi dwuma wɔ ɔhyew a ɛba fam mu ne sɛnea etumi gyina ɔsɛe ano.
(3) Wɔde TR10 di dwuma de susuw viscoelasticity ne crystallization nkɛntɛnso a rɔba nya wɔ ɔhyew a ɛba fam mu, na mpɛn pii no ɛda ɔhyew a ɛba fam sen biara a rɔba ade bi betumi akura ne elastic ahoɔden mu adi.
(4) TGem de dade waya a ɛyɛ torsional a ɛwɔ torsional constant a wonim di dwuma sɛ ade a wɔde twitwiw nhwɛsode no wɔ anim kɛse, bere a bere a ɔhyew no so tew no, rɔba no modulus kɔ soro, rigidity no kɔ soro, na angle of torsion no so tew kodu baabi a ɛkame ayɛ sɛ ɛnkyinkyim wɔ Tg. Rɔba no torsion angle sɛnea ɔhyew nsakrae te no betumi asusuw sɛnea ɔhyew a ɛba fam no yɛ adwuma no ho, na mpɛn pii no ɛkyerɛ ɔhyew a ɛba fam sen biara a rɔba no kura ne elasticity mu.
2 FKM Tg, TR10 ne abusuabɔ a ɛda Tbri ntam
FKM low-temperature embrittlement performance parameters a wɔtaa de di dwuma ne Tg, TR10 ne Tbri, adetɔnfoɔ no taa gye parameter Tg ne TR10, ASTM gye parameter Tbri, nsonsonoeɛ ne abusuabɔ bi wɔ saa mmiɛnsa yi ntam.
2. 1 Abusuabɔ a ɛda Tg ne TR10 ntam
TR10 a ɛwɔ FKM grade biara mu no bɛn Tg (nsonsonoe no ntra 3 °C), a ɛkyerɛ sɛ Tg ne TR10 nyinaa betumi ada ɔhyew a ɛba fam kankan ne ahwehwɛ tebea hyew a ɛwɔ rɔba molecule nkɔnsɔnkɔnsɔn mu adi.
2.2 Abusuabɔ a ɛda FKM fluorine dodow ne ɔhyew a ɛba fam mu embrittlement su ahorow ntam
Wɔ FKM abien ne abiɛsa a wɔtaa de di dwuma mu no, TR10 kɔ soro bere a fluorine dodow kɔ soro no; sɛ wɔde monomer a ɛto so anan, PMVE, ba a, emu nsɛm no nya TR10 so nkɛntɛnso kɛse.
Nea ɛwom no nya nkɛntɛnso kɛse wɔ TR10 so. Ɛwom sɛ fluorine dodow a ɛkɔ soro no betumi ama FKM a wɔde di dwuma hyew no anohyeto a ɛwɔ soro no atu mpɔn de, nanso bere koro no ara mu no, esiane CF nkitahodi no nti ɛhyɛ CH nkitahodi no ananmu, na ɛtew molecule nkɔnsɔnkɔnsɔn no brɛoo ne rɔba no adwumayɛ wɔ ɔhyew a ɛba fam so.
2.3 Nkɛntɛnso a fillers nya wɔ FKM nnuru a ɛma ɛyɛ hyew a ɛba fam no so
Carbon black N774 adhesive wɔ Tbri a ɛba fam sen biara na ɛko tia ɔhyew a ɛba fam yiye; zinc oxide adhesive na ɛwɔ Tbri a ɛkorɔn sen biara na ɛko tia ɔhyew a ɛba fam sen biara; sɛnea nneɛma a wɔde nkata so ahorow anum no yɛ adwuma wɔ ɔhyew a ɛba fam mu a ɛma ɛyɛ mmerɛw no nyɛ soronko koraa. Bere a wɔayɛ nhwehwɛmu awie no, bere a wɔde fillers ahorow aka ho akyi no, nsonsonoe ne nhyehyɛe a ɛda FKM molecule nkɔnsɔnkɔnsɔn ntam no yɛ soronko, na ɛsono sɛnea ɛne no hyia wɔ ɔhyew a ɛba fam mu embrittlement adwumayɛ.
Bere a wɔayɛ nhwehwɛmu awie no, bere a wɔde nneɛma ahorow a wɔde hyɛ mu aka ho akyi no, nsonsonoe ne nhyehyɛe a ɛda FKM molecule nkɔnsɔnkɔnsɔn ntam no yɛ soronko, na ɛsono sɛnea ɛne no hyia wɔ ɔhyew a ɛba fam mu embrittlement su ahorow, na nea wɔde hyɛ mu a rɔba kakraa bi wom no wɔ gel kɛse na ɛko tia ɔhyew a ɛba fam yiye.
2.4 Nsunsuansoɔ a ɛfiri afrafra kwan so wɔ FKM nnuru a ɛwɔ ɔhyew a ɛba fam mu no so
Ade a wɔde frafra no nso nya nkɛntɛnso wɔ FKM nnuru a ɛyɛ hyew a ɛba fam a ɛma ɛyɛ mmerɛw no so. Plastic a wɔde bɛhyɛ mu ansa na wɔafrafra no betumi ama rɔba molecule no ayɛ mmerɛw yiye
Wobetumi ama ɔhyew a ɛba fam a ɛwɔ aduru no mu no atu mpɔn denam plastic a wɔde bɛhyɛ mu ansa na wɔafrafra so. Thin pass treatment bere a wɔde compound no asi hɔ akyi no betumi ama fillers ne compatibilizers no apete su atu mpɔn, na ama ɔhyew a ɛba fam a ɛko tia no atu mpɔn. Sɛ yɛbɛka no ɔkwan biara so a, dodow a nsusuwso no kyɛ no, dodow no ara na Mooney viscosity a ɛwɔ rɔba no mu no so tew. Sɛ wɔma mmerɛ dodoɔ a wɔde yɛ nwene no kɔ soro a, ɛbɛtew rɔba no Tg so, nanso adeyɛ no nyɛ kɛseɛ, na nsonsonoeɛ kɛseɛ biara nni Tg ne Tbri a ɛwɔ FKM rɔba a ɛsono mmerɛ dodoɔ a wɔde yɛ nwene no ntam.
3 Awiei
(1) FKM Tg bɛn TR10 de no, a ebetumi ada ɔhyew a ɛba fam a ɛkɔ FKM molecule nkɔnsɔnkɔnsɔn ne ahwehwɛ tebea mu hyew adi, na Tbri no sua sen Tg ne TR10 de no.
no sua sen Tg ne TR10.
(2) Ɔhyew a ɛba fam embrittlement su a peroxide sulfurized high fluorine FKM yɛ papa, na ɔhyew a ɛba fam embrittlement su a bisphenol binary sulfurized FKM yɛ bɔne sen saa.
(3) FKM rɔba a wɔde carbon black N774 ahyɛ mu ma no tumi gyina ɔhyew a ɛba fam ano yiye; rɔba a wɔde filler kakraa bi ahyɛ mu no wɔ gel a ɛdɔɔso na ɛko tia ɔhyew a ɛba fam yiye.
(4) Mmere dodow a wɔde yɛ nkuku no nni nkɛntɛnso kɛse biara wɔ FKM nnuru a ɛma ɛyɛ hyew a ɛba fam no so.
