Silicone foam board ni hta 300℃jan katsi ai hpe lu la ai gaw, grai yak hkak ai lam ni hpe shabyin ya ai, hpa majaw nga yang, standard silicone arung arai ni gaw, galu kaba ai- aten hta jai lang ai aten hta, a{{3}60℃du hkra 200℃lapran bungli galaw nga ai, aten kadun na matu nbung katsi ai lam ni gaw 250℃du wa na masa nga ai. Ndai threshold hpe lai di ai shaloi, polymer backbone gaw hkrat sum hpang wa ai majaw, arung arai ni a daw garan ai lam, elasticity sum mat ai, hpang jahtum e pulverization byin wa ai.
300℃hta nbung katsi ai hpe ninghkap lu ai atsam hpe lu la na matu, madung arung arai, n-gun jaw ai ladat, n-gun n-gun- hpe ninghkap lu ai additives, foaming process hte structural design ni kaw na hkum tsup ai hkrang shapraw ai lam hte kaja dik htum hpe galaw ra ai.
Ndai yaw shada lam hpe lu la na matu madung hpaji masa ni hte myit sawn sumru ai lam ni gaw lawu na hte maren rai nga ai:
I. Core Material ni hpe lata la nna ra sharawng ai lam
Ndai gaw npawt nhpang dik htum ai lahkam rai nga ai.
Phenyl silicone rubber tsaw ai hpe lang u:
Principle: Ordinary silicone rubber (methyl vinyl silicone rubber) gaw katsi ai hpe ninghkap lu ai atsam n law ai. Siloxane main chain hta phenyl hpung ni (grau nna diphhenylsixane chain daw ni hta grai law ai) ni hpe hpaw hpang ai gaw, dai arai a katsi ai hpe ninghkap lu ai atsam hpe grai shatsaw ya lu ai.
Function: Benzene ring a n-gun kaba ai hkrang hte shi a conjugation effect gaw, katsi ai-sensitive Si-O matut mahkai lam hpe atsawm sha makawp maga ya lu nna, n-gun n-gun hpe n-gun jaw ya lu ai, dai hku nna, n-gun n-gun shayawm ai lam hte polymer chain a oxidative cleavage hpe pat shingdang lu ai. High{3}}}penyl silicone rubber gaw 250-3}300℃du hkra galu kaba ai nhtoi hte aten kadun nbung katsi ai hpe 350℃hta hkam sharang lu ai.
Fimed silica hpe n-gun jaw ai filler hku lang u:
Ra kadawn ai lam: N-gun n rawng ai silica gel gaw grai n-gun n law ai. Fumed silica (nanoscale silica) gaw silica gel ra ai n-gun hpe jaw ya lu ai n-gun shaja ya ai filler langai sha rai nga ai.
Ra kadawn ai lam ni: Laksan tsi lajang ai lam, kaji ai n-gun n-gun hte n-gun kaba ai lamu ga ntsa shara ni hpe lang ra ai. Dai gaw silica matrix hta n-gun ja ai nano{2}}network hkrang hpe hpaw ya lu nna, nbung laru kaba hta pyi, jak rung atsam nkau mi hpe n-gun jaw lu ai.
II. Hka lum ai hpe ninghkap lu ai additive system
Madung arung arai ni hpe sha kam hpa ai hte sha n law ai, laksan katsi ai- hpe bai gram lajang ai additives ni hpe "makawp maga ai hte escort" hta jat bang ra ai.
Katsi ai shara:
1)Iron oxide (Fe ; Dai hpraw ai n-gup hpe - n-gup n-gu -brown hpe lang ma ai. Dai gaw, siloxane shingdu hpe nbung laru kaba ai shara kaw gasat ai free radicals ni hpe rim la nna, grau ngang grin ai siloxane{{6}carbon structures ni byin pru wa ai hpe n-gun jaw ya ai, dai hku nna backbone hpe jahten kau ai hpe pat shingdang ya ai. Dai tsi gaw 0.5 kaw nna 3 du hkra rai nga ai.
2)Cerium oxide (CeO) gaw grai kaja ai n law htum n law htum earth- hpe n-gun n rawng ai hku hkam sharang lu ai, grau nna Fe₂Ocent hte hpawng de ai shaloi. Dai gaw silanol hpung ni a n-gun hte n-gun hpe hkrak hkra pat shingdang ya ai.
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Htap htuk ai vulcanization masa hpe lata la na:
1)Peroxide vulcanization: Foaming arung arai ni a matu, peroxides (bis(2,5{4}}teroxide zawn re ai ni a matu, n-gun n rawng ai tsi ni hpe lang ai. Dai majaw, n-gun n rawng ai arung arai ni hte n-gun n rawng ai arung arai ni lawm ai peroxide ni hpe lata na matu ahkyak nga ai, dai sha n-ga, n-gun ja ai nbung laru npu hta ngam nga ai arung arai ni hpe n hkra hkra, hkum tsup ai vulcanization hpe hkam la lu na matu.
2)Platinum sulfide (addition sulfide) gaw foam- hkrang shapraw ai lam ni ahkang jaw ai shaloi grau ra sharawng ai lata la ai lam re. Shi a cross{3}}linked Si-}C structure gaw, peroxide-}based system ni hta C{5}}}C matut mahkai lam ni hte shingdaw yang, grau kaja ai nbung n-gun hpe madun dan ai, n-gun n rawng ai lam n nga ai. Raitim, platinum- hta lawm ai system ni gaw, n-gun ja ai lam hte grup yin hpe hkang zing ai lam ni hpe ra sharawng nna, n-gun ja ai lam ni hpe ra sharawng nga ai.
III. Foaming galaw ai lam ni a lit ni
Nbung laru hpe ninghkap lu ai atsam kaba hpe hkan tam ai shaloi, langai sha re ai hte ngang grin ai foaming structure hpe mung lu la ra ai.
Chemical foaming agent: Decomposition temperature gaw vulcanization nbung laru hte maren rai ra ai, decomposition galaw ai arung arai gaw inert gas (sattrogen zawn re ai) rai ra ai. Decomposition ngam ai gaw silica gel matrix a hkrat sum ai lam hpe n-gun n jaw ging ai.
Hkum hkrang n-gun jaw ai lam: Supercritical fluid foaming zawn re ai hpaji masa ni gaw, tsi mawan ni hpe n-gun jaw ai tsi mawan ngam ai manghkang hpe koi lu ai, raitim, jak rung ni a gumhpraw bang ai lam gaw kaba ai hte, dai lam gaw grai sawng ai.
Key point: Gara foaming ladat hpe lang tim, cell structure gaw ngang grin nna, cell bunghku hpe n-gun ja hkra galaw na matu ra ai. Open cell structure (sh) n-gun kya ai cell bunghku gaw nbung laru kaba hta lawan ai hku hkrat sum mat na re majaw, nbung n-gun shayawm ai lam grai yawm mat na re.
IV. Structure hte Post{1}} Hkrang shapraw ai hkrang shapraw ai lam
Density hpe jat wa/Ruce bubbles hpe jat bang u: N-gun hte n-gun n-gun hpe hkan sa na ngu ai ningmu hta, foam board a density hpe hkrak hkra jat wa shangun ai (dai gaw, foaming ratio hpe shayawm ai) gaw grau galu ai hte katsi ai- hpe n-gun ja ai hka htung bunghku hpe lu la mai ai, dai hku nna, nbung laru hpe ninghkap lu ai atsam hte jak rung n-gun yawng hpe grau kaja hkra galaw ya lu ai.
Composite structure: Ga shadawn, "sandwich" hkrang hpe galaw na matu myit yu u, maga lahkawng hpe n-gun kaba ai- n-gun ja ai non{1}}} porous silicone sumla hkrung (sh) glass fiber hpun palawng hte galaw da ai, lapran kaw foamed layer langai mi nga ai. Ndai lam gaw, n-gun n rawng ai porous structure hpe makawp maga ya lu ai.
Post{0}}high temperature vulcanization: N-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun hpe tsep kawp yeng seng kau na matu hte crosslinking network hpe ngang grin hkra galaw na matu, n-gun n-gun n-gun n-gun n-gun n-gun hpe tsep kawp yeng seng kau lu na matu, n-gun n-gun n-gun n-gun hpe n-gun jaw ai (ga shadawn, 200{5}}250℃hta hkying hkum law law tup n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun n-gun hpe shayawm kau ra ai.