NBR foam (nitrile rubber foam) leh silicone foam (silicone rubber foam), rubber-based foam material hman lar tak pahnih an nih angin, an molecular structure leh chemical reaction mechanism hrang hrang avang hian core foaming principle leh material property te chu a bulpui berah a inang lo hle a ni. Heng danglamna te hian industrial application-a material tinte thlan dan tur chu direct-in a hril a ni.
A core foaming mechanism thlirna atang chuan NBR foaming hi high-temperature decomposition chemical foaming leh sulfur vulcanization cross-linking te synergistic action ah a innghat a ni. NBR molecular backbone hi carbon-carbon bonds (C–C) atanga siam a ni a, side group-ah chuan acrylonitrile (-CN) leh butadiene double bonds (C=C) te a awm a ni. A foaming process hi heterogeneous nucleation thermal decomposition foaming category-ah a tel a ni. Industrial production-ah chuan azodicarbonamide (AC), sodium bicarbonate, emaw N,N'-dinitrosopyramidetetramine (DPT) te hi blowing agent atan hman a ni tlangpui. Temperature 150–180℃-a a san chuan heng blowing agents te hian thermal decomposition an tawk a, gas N2, CO2, leh NH3 te an chhuah tir thin. Heng gas te hi NBR melt chhungah an inzar pharh a, pores an siam thin. Chutih rual chuan sulfur vulcanization reaction te hi a rualin a thleng a, chu chuan butadiene double bonds te cross-linking a thlen a, C–C leh C–S–C network structure a siam a, a tawpah chuan pore morphology chu a ti nghet ta a ni. He cross{16}}linked network bulpui ber chu sulfur bridge hmanga carbon-carbon bonds inkara bridging interaction-ah a awm a, cross-linking bonds hi C–S–C leh single/double sulfur bonds atanga siam a ni ber. Bond energy an neih tlem avangin heng network te hian thermal stability an nei tlem hle.
Chumi danglamna chu foam silicone-a foaming mechanism hian platinum-catalyzed cross-linking leh foaming laiin in situ hydrogen evolution synchronous reaction a nei a, chu chuan homogeneous nucleation-based reactive foaming system a siam a ni. Foam silicone matrix chu polydimethylsiloxane (PDMS) a ni a, molecular backbone chu silicon-oxygen bonds (Si–O–Si) leh methyl side group (–CH3) atanga siam a ni. Foaming leh curing hi a tlangpuiin two-component system hmanga tih theih a ni: Component A hi Si–CH=CH2 awmna vinyl silicone oil a ni a, Component B erawh chu hydrogen- awmna silicone oil Si–H bonds nei leh platinum catalyst a ni thung. Reaction chhung hian thil pawimawh tak tak pahnih a rualin a thleng a: pakhatnaah chuan platinum-catalyzed cross-linking reaction a ni a, chutah chuan Si–CH=CH2 chu Si–H nen a inzawm a, Si–C bonds a siam a, chu chuan colloid curing a siam thei a pahnihnaah chuan hydrogen evolution foaming reaction a ni a, chutah chuan Si–H chu Si–OH nen an inrem a, Si–O–Si bonds a siam a, H2 a chhuah tir a ni. Hydrogen hi polymer matrix chhungah nucleate leh expand a ni a, a tawpah chuan closed-cell emaw open-cell structure emaw a siam ta a ni. Cross-linked network hi Si–O–Si main chain leh Si–C cross-links vel a ni a, Si–O bonds hian NBR-a C–C bonds 347 kJ/mol aiin energy 452 kJ/mol thlenga sang zawk a lantir a, chu chuan foam silicone exceptional thermal stability a tichiang a ni (PMC, 2025; MDPI, 2024) te chuan an ziak a ni.
Material property lamah chuan material pahnih inthlauhna hi key indicator-ah a lang ber a, chungte chu temperature resistance, chemical resistance, mechanical property, leh environment stability te hi a ni. Fundamental physical perspective atang chuan NBR foam hian density 0.3–0.8 g/cm3 a nei a, Shore A hardness chu 20–70℃a nei a, a tam zawk chu closed-cell structure a ni a, pore size 50–300 μm inkar a ni a, porosity chu 40–70% a ni. Chumi danglamna chu foamed silicone hian density hniam zawk (0.2–1.1 g/cm3), hardness nem zawk (Shore A 1–50℃), pore size inang zawk (20–100 μm), leh porosity sang zawk (50–80%) a nei a ni. Experimental data atanga a lan dan chuan a pore size consistency chu NBR foam aiin 40% in a sang zawk a ni (MDPI, 2024; PMC, 2025).
Thermal resistance hi thil pahnih inthlauhna bulpui ber pakhat a ni. NBR foam hian long-term service temperature range –30℃atanga +120℃a nei a, heat loss weight 5% chu 280℃vel ah a thleng thin. Darkar 72 chhung 150 degree-a a upa hnuah a khauh a, 10–15%-in a tlahniam a, 50% aia tam elasticity a hloh bawk. Chumi danglamna chu foam silicone hian hun rei tak-hun hmanna temperature –60℃atanga +230℃thleng a tuar thei a, hun rei lote-a 280℃thlenga hman a tuar thei a, heat loss weight 5% chu 480℃vel ah a thleng thei a ni. Darkar 72 chhung 200 degree-a a upa hnuah pawh a permanent compression deformation chu 30% aia tlem emaw, a tlukpui emaw a ni reng a, a elastic retention pawh 70% aia tam a ni (data from Solid Rocket Technology, 2019). Hetianga danglamna awm chhan bulpui ber chu chemical bond chakna inang lo vang a ni: Si–O bonds stability sang tak hian silicone chu temperature sang zawk-temperature condition hnuaiah degradation a do thei a ni.
Temperature resistance chungchangah chuan Chinese enterprise pakhat chuan foam silicone an siam a, hei hian hun rei lote chhung temperature 315℃a tuar thei a ni.
Chemical resistance lamah chuan NBR foam hian oil resistance mak tak a nei a, foamed silicone hian acid, alkalis, ozone, leh ultraviolet radiation lakah pawh performance ropui tak a lantir thung. Wiley (2019) atanga experimental data atanga a lan dan chuan #3 engine oil-a 100 degree-a darkar 72 chhung an thun hnuah NBR foam volume change chu 2.1% chauh a ni a, hei hian mineral oil, engine oil, leh diesel fuel te a tuar thiamna tha tak a tilang a, chubakah aromatics leh esters te pawh a do tha hle tih a tilang bawk mahse, acid, alkali leh tui lakah a performance chu a average a ni. Chumi danglamna chu, foamed silicone hian condition inangah volume expansion rate 42.7% thleng a lantir a, oil resistance tha lo mahse acids, alkalis, tui, ozone, leh UV radiation laka exceptional tolerance a lantir a, outdoor service life kum 20–30 chhung chu tar lovin a nei thei a ni. Chumi nena khaikhin chuan NBR foam hian pawn lamah kum 3–5 chauh a dam thei a, ozone aging hnuah cracking a nei (50 ppm, 40℃, 72 h), UV aging darkar 300 chhung chuan hardening, brittleness, leh surface powdering a thlen thung (data cited from Journal of Wuhan University, 2022).
Mechanical property lamah chuan NBR foam hian tensile strength sang zawk (0.8–2.5 MPa), permanent compression deformation (25%,72 h, 70℃) 25% aia tlem emaw, a tlukpui emaw, leh resilience hniam zawk (50–60%) a nei a ni. Foamed silicone hian tensile strength (0.5–0.8 MPa) tlem zawk (0.5–0.8 MPa) mahse break-ah elongation sang zawk (>=300%) leh superior resilience (70–85%) a lantir a, high-temperature conditions-a permanent compression deformation chu 200 degree-ah 30% hnuai lamah a awm reng a ni (Journal of Wuhan University, 2022 atanga data lak chhuah a ni). Flame retardancy leh safety chungchangah chuan NBR foam hian flame retardants a mamawh a, chu chuan flame resistance leh self-extinguishing property a neih theih nan flame atanga lakchhuah a nih veleh flame retardants a mamawh a a kang laiin meikhu dense tak a siam a, toxic gas CN− leh SO2 te a chhuah bawk. Chumi danglamna chu foamed silicone hian intrinsic flame retardancy a nei a, UL94 V-0 standards a tlin a, non-flammable, smoke-free, leh non-toxic/odorless, food-grade requirements (FDA 21 CFR 177.2600) zawm a ni.
A tawi zawngin, NBR foam leh foamed silicone inthlauhna hi an bulpui berah chuan an molecular structure hrang hrang leh foaming/cross{0}}linking mechanism atanga lo chhuak a ni: NBR foam hi carbon chain-based a ni a, sulfur vulcanization leh thermal decomposition hmangin a pianzia a thleng thei a, oil resistance chak tak leh man tlawm zawk a pe a, mahse temperature resistance leh environment stability tlem zawk a pe a foamed silicone hi silicon-oxygen backbone-ah a innghat a, chutah chuan platinum-in a catalyzed cross-linking chu foaming laiin hydrogen evolution nen a rualin a thleng a, temperature resistance, aging resistance leh safety danglam tak a lantir a, mahse oil resistance tha lo zawk leh man to zawk nei mahse. Heng characteristic danglamna te hian material tinte tana application scenario chiang takin a tarlang a, industrial selection atan pawh a bulpui nghet tak a pe bawk.
Weather i hriat chian loh chuan NBR foam leh silicone foam hmang la , datasheet leh The Latest Development Trends of silicone sponge sheet dawng turin min contract thei ang