Fluoroelastomer (FKM) chhiatna langsar tak chu low temperature resistance tha lo hi a ni. Binary FKM-a low-temperature retraction temperature (TR10) chu a tlangpuiin -18 atanga -16 °C a ni a, glass transition temperature (Tg) chu -20 °C a ni a; ternary FKM-a low-temperature resistance chu binary FKM aiin a chhe zawk. Special low-temperature type FKM hian low-temperature resistance tha tak a nei a, mahse a man a to hle.
FKM in ASTM D 2000-2012 'automotive rubber products standard classification system' ah M2, M5, M6 grade products te chu low-temperature embrittlement F15 (-25 °C) test pass tur chuan a ngai a, M4 grade products te chu low-temperature embrittlement F17 (-40 °C) test pass turin a ngai a ni. Tun hnaiah FKM product tam zawk chu high temperature resistance (250-275 °C) leh low temperature embrittlement F15 emaw F17 emaw te mamawh phuhruk turin a mamawh a ni. A tha ber chu low-temperature FKM hman a ni a, chu chu brittleness temperature -45 ~ -40 °C Viton GLT type FKM a ni a, mahse he FKM high-temperature performance hi a tha lo a, a man pawh market pawmtlak siam a harsa hle. Binary FKM compound performance tihchangtlun hian a rualin temperature hniam leh sang resistance mamawh a phuhruk thei a, a man pawh a tlawm bawk a, hei hi research hot spot a lo ni ta a ni.
He paper hian Tg, TR10 leh brittleness temperature (Tbri) te FKM low-temperature performance characterization te chu postgraduate zirlai, fillers, mixing process, etc. te inzawmna te chu binary leh ternary FKM adhesive low-temperature brittleness performance atan low-temperature-resistant FKM adhesive buatsaih nan reference pe turin a zirchiang a ni!
1. FKM low-temperature embrittlement property te characterization
Rubber hian reversible deformation a nei a, pawn lam chakna tlemte hnathawhna hnuaiah deformation lian tak a siam thei a, pawn lam chakna a lak chhuah hnuah a dinhmun hmasaah a awm leh thei a, chuvangin hman a ni nasa hle. Mahse, temperature a tlahniam chuan rubber elasticity a chhe zauh zauh a, Tg a thlen chuan rubber hian a elasticity a hloh a, a fail ta a ni. Rubber thil chi hrang hrang a awm avangin, hmanna kawngah hian impact, tension, shear, torsion, extrusion, abrasion, etc. a tawk thei a, a low-temperature embrittlement performance chu a hnathawh dan atanga thlirin test dan dik tak thlan tur a ni. Low-temperature embrittlement performance test hman tlanglawn tak takte chu Tg test, impact brittleness temperature test, low-temperature retraction test, low-temperature torsional rigidity test (Gimen test), resistance to stretching leh cold coefficient test, low-temperature hardness test, low-temperature compression permanent deformation leh stress relaxation test, etc. te a ni.
FKM hian temperature hniam a resistance hi Tg, Tbri, TR10 leh Torsion Temperature at low temperature (TGem), etc. te hian a hriat theih a, heng parameter te hian awmzia hrang hrang nei mahse inzawmna engemaw tak an nei a ni.
(1) Tg chu rubber chu elastic state sang tak atanga glassy state-a a inthlakna temperature a ni a, glassy state atanga elastic state sang takah a inthlakna temperature a ni a, hei hian rubber molecular chain-te microscopic movement a lantir tlangpui a ni.
(2) Tbri chu impact force deformation dinhmun tarlan hnuaia rubber-a chhiatna awm lohna temperature a ni a, hei hian temperature hniam taka hman tur rubber chakna leh chhiatna a tuar theih dan a lantir tlangpui.
(3) TR10 hi temperature hniam takah rubber viscoelasticity leh crystallization effect tehna atan hman a ni a, a tlangpuiin rubber material pakhatin a elastic recovery a vawn theihna tur temperature hniam ber a lantir thin.
(4) TGem hian torsional steel wire, torsional constant hriat lar tak chu reference material atan a hmang a, specimen chu angle lian takah a twist a, chutih laiin temperature a tlahniam chuan rubber modulus a sang a, rigidity a sang a, torsion angle chu Tg. Rubber temperature inthlak dan azirin a torsion angle hian a temperature hniam performance a evaluate thei a, a tlangpuiin rubber hian a elasticity a vawn thatna temperature hniam ber a lantir thin.
2 FKM Tg, TR10 leh Tbri inzawmna te
FKM low-temperature embrittlement performance parameter hman tlanglawn tak chu Tg, TR10 leh Tbri te an ni a, supplier hian parameter Tg leh TR10 a hmang tlangpui a, ASTM hian parameter Tbri a hmang a, heng pathum inkarah hian danglamna leh inzawmna engemaw zat a awm.
2. 1 Tg leh TR10 inzawmna
FKM grade tina TR10 hi Tg nen a inhnaih hle (a danglamna chu 3 °C aia tam a ni lo), hei hian Tg leh TR10 te hian rubber molecular chain-a low-temperature movement leh glass state temperature an lantir thei tih a tilang a ni.
2.2 FKM fluorine awm zat leh low-temperature embrittlement property inzawmna
Common binary leh ternary FKM-ah chuan TR10 hi fluorine awm zat a san chuan a pung a; monomer palina, PMVE an rawn luh chuan a chhunga thil awmte hian TR10-ah nghawng lian tak a nei a ni.
A thupui hian TR10-ah nghawng lian tak a nei a ni. Fluorine content tihpun hian FKM hmanna temperature upper limit a ti tha thei a, mahse chutih rual chuan CF bond avang hian CH bond a thlak a, molecular chain softness leh rubber low-temperature performance a tihhniam bawk.
2.3 FKM compound-te temperature hniam taka embrittlement property-a filler-te nghawng
Carbon black N774 adhesive hian Tbri a nei hniam ber a, low-temperature resistance tha ber a nei bawk; zinc oxide adhesive hian Tbri a nei sang ber a, low-temperature resistance a chhe ber bawk; adhesive chi pangate low-temperature embrittlement performance hi a danglam vak lo. Analyse hnuah filler hrang hrang dah hnuah FKM molecular chain inkar gap leh structure chu a danglam a, a inmil low-temperature embrittlement performance pawh a danglam bawk.
Analyse hnuah filler hrang hrang dah hnuah FKM molecular chain inkar gap leh structure te chu a danglam a, a inmil low-temperature embrittlement property pawh a danglam a, rubber tlemte awmna filler hian gel content lian zawk leh low-temperature resistance tha zawk a nei bawk.
2.4 FKM compound-te low-temperature embrittlement property-a mixing process-in nghawng a neih dan
Mixing process hian FKM compound te low-temperature embrittlement property ah pawh nghawng a nei a ni. Mixing hmaa plasticize hian rubber molecule flexibility a hmu tha zawk thei
Compound temperature hniam tak a resistance chu mixing hmain plasticize hmangin a ti tha thei a ni. Compound park hnua thin pass treatment hian filler leh compatibilizer te dispersion property a ti tha thei a, low-temperature resistance pawh a ti tha thei bawk. A tlangpuiin, molding a rei poh leh rubber-a Mooney viscosity a hniam zawk. Moulding time tihpun hian rubber Tg a tihtlem phah dawn a, mahse phenomenon hi a langsar lo hle a, FKM rubber molding time number hrang hrang nei Tg leh Tbri te hi a danglamna lian tham a awm lo.
3 Thutawp
(1) FKM Tg hi TR10 nen a inhnaih a, hei hian FKM molecular chain leh glass state temperature temperature hniam tak a lantir thei a, Tbri chu Tg leh TR10 aiin a hniam zawk bawk.
Tg leh TR10 aiin a hniam zawk.
(2) Peroxide sulfurized high fluorine FKM-a low temperature embrittlement property chu a tha zawk a, bisphenol binary sulfurized FKM-a low temperature embrittlement property chu a chhe zawk bawk.
(3) Carbon black N774-a khat FKM rubber hian temperature hniam lama a do theihna tha zawk a nei a; rubber filler tlemte nen hian gel content a sang zawk a, low-temperature resistance tha zawk a nei bawk.
(4) Moulding time awm zat hian FKM compound-te low-temperature embrittlement property-ah nghawng a nei tlem hle.
