Ke hoʻohālikelike nei i nā Isocyanates me nā Reactive Liquid Rubbers HTPB a me CTBN

Nā Manaʻo Koʻikoʻi

• E hoʻohui i nā laholio wai non-polar me nā isocyanates ʻala e hana i nā mea kū i ka wai a me ka ikaika kiʻekiʻe.
• E hoʻohui i nā isocyanates aliphatic me nā rubbers wai e hana i nā sila maopopo a pale i ka wā e kūʻē i ka pōʻino o ka lā.
• E mālama i kāu Kemika NCO helu kuhikuhi ma waena o 1.02 a me 1.08 e hōʻoia i ka hoʻōla piha ʻana a me ka hana ikaika.

Kemika a me ka Palapala ʻĀina Hana

Ka Hana Hou ʻana o ka Pūʻulu Terminal a me Kinetics

Pono ʻoe e hoʻohālikelike i ka wikiwiki o ka hopena o kāu isocyanate i koho ʻia i nā hui hope kikoʻī o kāu laholio wai. ʻO ka polibutadiene i hoʻopau ʻia me ka hydroxyl (HTPB) pane mālie me nā diisocyanates, ʻoiai nā ʻūpā i hoʻopau ʻia me ka amine (ATBN) pane koke e hana i nā pilina polyurea ikaika. Ke hoʻokumu ʻoe i nā diisocyanates asymmetrical e like me IPDI, hoʻololi nā mea hoʻoulu kikoʻī i ka hana hui. No ka laʻana, hoʻāla koho ka waikawa trifluoroacetic i ka hui isocyanate mua ma luna o ka lua. ʻO ke ʻano kemika o nā hui ʻaoʻao e pili ana e hoʻokele i kēia koho kinetic ma mua o ka pale steric.

Hoʻohālikelike ʻana o ka Polarity a me ka Solubility Parameter

ʻO ka hoʻohālikelike ʻana i nā Isocyanates me nā Reactive Liquid Rubbers (HTPB vs. CTBN) pono e loiloi pono i nā ʻano solubility. Kūʻē nā iwi kuamoʻo polibutadiene non-polar i ka hui pū ʻana me nā polar, aromatic isocyanates. Hiki iā ʻoe ke hoʻohana i ke alakaʻi aʻe e hoʻopili i nā iwi kuamoʻo me nā curatives:

ʻO ke Geometry Isocyanate a me ke ʻano o ka ʻāpana paʻakikī

ʻO ka symmetry molecular Isocyanate e hoʻoholo i ka crystallization ʻāpana paʻakikī a me ka hoʻokaʻawale ʻana o ka pae. Hoʻopili paʻa nā ʻano aromatic symmetric e like me 4,4'-MDI, e hana ana i nā kikowaena paʻa e hoʻonui ai i ka ikaika mechanical. ʻO nā monomers Asymmetric e like me TDI a i ʻole IPDI e hoʻopilikia i ka hoʻopaʻa ʻana, e hoʻohaʻahaʻa ana i ka viscosity resin a hoʻonui i ka elasticity haʻahaʻa haʻahaʻa. Hiki iā ʻoe ke hoʻomaikaʻi i ka paʻakikī polymer holoʻokoʻa ma ke kaulike ʻana i nā geometries symmetric a me asymmetric.

Ke hoʻohālikelike nei i nā Isocyanates me nā Reactive Liquid Rubbers (HTPB Systems)

Loaʻa i ka Hydroxyl-terminated polibutadiene (HTPB) kahi iwi kuamoʻo hydrocarbon non-polar kiʻekiʻe loa. Pono ʻoe e koho i nā curatives kūpono e hoʻopaʻa i ke kūpaʻa o ka makū a mālama i ka pono o ke kūkulu ʻana. ʻO ka hoʻohālikelike ʻana i nā Isocyanates me nā Reactive Liquid Rubbers (nā ʻōnaehana HTPB e pono ai ka nānā ʻana i ka reactivity kemika a me nā koi mechanical hope loa.

MDI a me TDI no nā Elastomers Hydrophobic

ʻO nā diisocyanates ʻala e like me ʻo diphenylmethane diisocyanate (MDI) a me toluene diisocyanate (TDI) pane koke me nā hui hopena HTPB hydroxyl. Hāʻawi kēia mau ʻano ʻala i ka ikaika kino kūikawā a me ke kumukūʻai haʻahaʻa. Hoʻokumu ʻo MDI i nā ʻāpana paʻakikī paʻa a crystalline kiʻekiʻe i loko o ka pūnaewele elastomeric. Hoʻonui kēia ʻūlū paʻa i ka ikaika tensile a hoʻonui i ke kū'ē ʻana i ka haehae.

HTPB Backbone (ʻAʻole polar) + MDI/TDI (ʻAla) ===> Hydrophobic Structural Elastomer 

Hāʻawi ʻo TDI i ka mānoanoa mua haʻahaʻa ma mua o MDI. Hiki iā ʻoe ke ninini maʻalahi i nā ʻano hana TDI i loko o nā ʻōmole paʻakikī. Eia nō naʻe, hōʻike ʻo TDI i ke kaomi mahu kiʻekiʻe. Pono ʻoe e lawelawe iā TDI me ka ea hou aʻe e pale aku i nā mea hoʻohana.

Mālama nā mea ho'ōla ʻala ʻelua i nā ʻano kūlohelohe o HTPB e pale aku i ka wai. Pale lākou i kāu elastomer hope loa mai ka omo ʻana o ka wai, nā waikawa dilute, a me nā alkalis aqueous.

Hoʻomaopopo: Hoʻopau ʻia nā ʻāpana paʻakikī ʻala ma lalo o ke kukui ultraviolet (UV) pololei. E hoʻohana i ka MDI a me TDI ma nā noi i kanu ʻia, i uhi ʻia, a i ʻole i loko o ka hale kahi e emi ai ka ʻike ʻana o ka UV.

ʻO IPDI a me HDI no nā ʻano hana paʻa māmā

Hoʻoponopono nā isocyanates aliphatic i ka ʻelemakule wela a me nā pilikia hōʻino māmā. Kūʻē loa ʻo Isophorone diisocyanate (IPDI) a me hexamethylene diisocyanate (HDI) i ka kukuna UV. Pale lākou i ka melemele o ka ʻili a me ka nahā i ka wā lōʻihi o ka ʻike ʻana i waho.

Loaʻa i ka IPDI ʻelua mau hui NCO like ʻole. Hoʻololi mālie ka hui NCO mua, ʻoiai ʻoi aku ka wikiwiki o ka hui NCO lua ma lalo o nā mahana kiʻekiʻe. Hiki iā ʻoe ke hoʻohana i kēia ʻokoʻa kinetic e kāohi i kāu ola pot-life a me ke kaʻina hana hoʻolei.

Hāʻawi ʻo HDI i ka maʻalahi linear. ʻO kona ʻano aliphatic symmetrical e hōʻemi ana i nā mahana hoʻokaʻawale microphase, kahi e mālama ai i ka elasticity a hiki i nā kūlana sub-zero.

• Nā pōmaikaʻi o ka IPDI: Hoʻolōʻihi ʻia ke ola o ka ipu hao, nā pōʻaiapuni hoʻōla hiki ke hoʻokele ʻia, ke kūpaʻa wela kiʻekiʻe.
• Nā pono o ka HDI: ʻOi aku ka maʻalahi o ka mahana haʻahaʻa, ke kūpaʻa UV maikaʻi loa, ka viscosity haʻahaʻa.

ʻO ka hoʻohālikelike ʻana i nā Isocyanates me nā Reactive Liquid Rubbers (HTPB a me nā aliphatic curatives e hoʻopuka i ka mōakāka optical, ke kūpaʻa kala, a me nā sila kūpaʻa i ka wā.

ʻO ka hana ʻana o ka Prepolymer a me ka hoʻonui ʻana i ka Stoichiometry

Hiki i ka hoʻohuihui pololei ʻana i hoʻokahi pana ke hana i nā hopena exothermic i kāohi ʻole ʻia a me ka hoʻokaʻawale ʻana o ka pae. Hiki iā ʻoe ke pale i kēia mau pilikia ma ka synthesizing a ʻO ka prepolymer i hoʻopau ʻia e ka NCO mua. Hoʻohaʻahaʻa ka synthesis prepolymer i ka hana wela holoʻokoʻa i ka wā o ka hoʻōla hope loa a hōʻemi i nā hoʻokuʻu monomer volatile.

1. Hoʻomākaukau ʻana i ka hopena: E hoʻopiha i kāu reactor me ka resin HTPB maloʻo.
2. Wehe ʻana i ka makū: Hoʻohemo ʻia ka resin ma ka vacuum ma 90°C e hoʻopau i ke koena o ka makū. Hoʻopili ka wai me nā hui NCO, e hana ana i nā pehu kalapona dioxide a me nā wahi nāwaliwali o ka urea.
3. Hoʻohui Isocyanate: E hoʻohui i kāu diisocyanate i koho ʻia ma lalo o kahi pāpale naikokene maloʻo.
4. Hoʻonui Kaulahao i kāohi ʻia: E mālama i ka mahana ma waena o 70°C a me 80°C a hiki i ka paʻa ʻana o ka nui o ka NCO.

KaʻAnuʻu Hana 1: Isocyanate Keu + HTPB ===> NCO-Terminated Prepolymer + Free Monomer KaʻAnuʻu Hana 2: Prepolymer + Chain Extender ===> Cured Polyurethane Network 

Pono ʻoe e helu pono i kāu stoichiometry. E mālama pono i ka helu NCO holoʻokoʻa (lakio like o nā hui NCO i OH) i loko o ka pae 1.03 a 1.06.

$$\text{Pane Kuhikuhi NCO} = \frac{\text{Huina like o NCO}}{\text{Huina like o OH}}$$

ʻO kahi helu kuhikuhi NCO ma lalo o 1.00 e waiho ana i nā kaulahao HTPB i pane ʻole ʻia. Hana kēia mau mole wai i pane ʻole ʻia ma ke ʻano he plasticizers makemake ʻole ʻia, kahi e hoʻohaʻahaʻa ai i kāu modulus tensile a hoʻohaʻahaʻa i ke kūpaʻa kemika. I ka ʻaoʻao ʻē aʻe, ʻo kahi helu kuhikuhi NCO ma luna o 1.10 e hana i ka crosslinking nui loa. ʻO ka nui o nā crosslinks e hoʻoulu ai i ka hāʻule ʻana o ka brittle ma lalo o ka hoʻouka hopena dynamic. ʻO ka stoichiometry pololei e hōʻoiaʻiʻo i ka hana kiʻekiʻe loa.

Nā Hoʻolālā Koho CTBN, ATBN, a me HTBN

Pono nā hui hope carboxyl, amine, a me hydroxyl ma nā iwi kuamoʻo nitrile rubber i nā hoʻolālā koho i kuhikuhi ʻia. Hiki iā ʻoe ke hoʻomaikaʻi nui i ka paʻakikī o ka haki, ke kūpaʻa kemika, a me ka hana wela ma ka hoʻopili ʻana i kēia mau rubbers functionalized me nā isocyanates kūpono.

Nā Hybrids Epoxy-Polyurethane me CTBN a me MDI

Loaʻa i ka Carboxyl-terminated butadiene acrylonitrile (CTBN) nā hui waikawa carboxylic terminal (-COOH) a me kahi iwi kuamoʻo nitrile polar. ʻO nā hopena pololei ma waena o nā waikawa carboxylic a me nā diisocyanates e hoʻopuka i nā pilina anhydride paʻa ʻole a hoʻokuʻu i ke kinoea carbon dioxide. Hiki iā ʻoe ke hoʻopau i nā pehu kinoea ma ka synthesizing epoxy-polyurethane hybrid networks.

CTBN + Resin Epoxy keu ===> Prepolymer Lahopa i hoʻopau ʻia me ka Epoxy Prepolymer Epoxy + 4,4'-MDI + Mea Hoʻolōʻihi Kaulahao ===> Matrix Hybrid Toughened 

ʻO ka mea mua, e hoʻopili iā CTBN me ka resin epoxy keu e loaʻa ai kahi waena rubber i hoʻopau ʻia e ka epoxy. A laila, e hoʻohui i ka 4,4'-MDI a me kahi mea hoʻolōʻihi kaulahao diol e kūkulu i kahi iwi kuamoʻo polyurethane crosslinked a puni nā ʻāpana rubber.

Manaʻo kōkua akamai: E mālama i ka nui o ka acrylonitrile (AN) i loko CTBN ma waena o 18% a me 26%. Paipai kēia pae AN kikoʻī i ka hoʻokaʻawale ʻana o ka pae i ka wā e hoʻōla ai. Hoʻopuka ʻia nā ʻāpana laholio liʻiliʻi e like me ka micron mai loko mai o ka matrix, e hana ana i nā pale kūpono e kūʻē i ka laha ʻana o ka māwae.

Hāʻawi ʻo MDI i nā ʻāpana paʻakikī ʻala ikaika e hoʻopaʻa ai i ka matrix polar. Ke pā ka hoʻoluhi ikaika i ka hybrid i hoʻōla ʻia, hoʻopili kēia mau kikowaena CTBN i hoʻopuehu ʻia i ka ikehu hopena. Loaʻa iā ʻoe ka paʻakikī haki kiʻekiʻe me ka ʻole o ka mōhai ʻana i ke kūpaʻa mechanical thermal a i ʻole ka modulus tensile.

Hoʻokumu pololei ʻia ʻo Amine-Isocyanate Urea me ATBN

ʻO ka Amine-terminated butadiene acrylonitrile (ATBN) he mau hui hopena amine mua a lua paha (-NH2 a i ʻole -NHR). Hoʻopili koke nā Amines me nā diisocyanates i ka mahana o ka lumi. Hoʻokumu lākou i nā pilina polyurea ikaika me ka ʻole o ka koi ʻana i nā catalysts synthetic.

I ka hoʻohālikelike ʻana i nā Isocyanates me nā Reactive Liquid Rubbers (Nā ʻōnaehana HTPB a i ʻole nā ​​​​ʻōnaehana ATBN), pono ʻoe e hoʻoponopono i kāu lako hoʻohuihui e lawelawe i kēia mau ʻokoʻa kinetic. Pane wikiwiki ʻo ATBN a pono ʻoe e hoʻohana i nā poʻo hoʻohuihui impingement kiʻekiʻe kūikawā.

ATBN (Nā Hopena Amine) + Isocyanate (NCO) ===> Nā ʻĀpana Paʻakikī Polyurea (Hoʻopaʻa Bidentate) 

Hoʻokumu nā ʻāpana paʻakikī polyurea i nā pilina hydrogen bidentate ikaika. Hoʻokiʻekiʻe kēia mau crosslinks kino i ka kiko degradation thermal o kāu elastomer ma luna o 150°C. Hoʻopau pū ʻoe i nā pilikia maʻi makū i ka wā o ka hana ʻana. Hoʻopili wikiwiki nā hui hopena Amine me NCO ma mua o ka wai ambient.

Ka Hoʻohālikelike ʻana o HTBN i nā ʻōnaehana pale wahie

ʻO ka butadiene acrylonitrile i hoʻopau ʻia me ka hydroxyl (HTBN) Hoʻohui i ka hana hydroxyl (-OH) me kahi iwi kuamoʻo nitrile polar. Hāʻule koke nā ʻōpala non-polar i ka wā e hōʻike ʻia ai i nā wahie non-polar, nā mea hoʻoheheʻe ʻala, a i ʻole nā ​​​​wai hydraulic. Hoʻokuke nā hui acrylonitrile polar i HTBN i nā hydrocarbons, e pale ana i kāu elastomer mai ka pehu ʻana o ka solvent.

HTBN (Polar Backbone) + IPDI/MDI ===> Pale Hydrocarbon Kūpaʻa Wahie 

Pono ʻoe e hoʻohālikelike i ka HTBN me nā diisocyanates kūpono e hana i nā sila paʻa, nā gaskets, a me nā liners pahu wahie:

• E hoʻohui iā HTBN me MDI: Loaʻa iā ʻoe ka paʻakikī mechanical kiʻekiʻe loa, ke kūpaʻa kiʻekiʻe o ka haehae, a me ka ikaika ʻōmaʻomaʻo wikiwiki no nā gaskets ʻoihana.
• E hoʻohui iā HTBN me IPDI: Loaʻa iā ʻoe nā uhi pahu wahie maʻalahi, paʻa i ka UV e kūʻē i ka nahā ma lalo o nā loli mahana ikaika.

Hiki iā ʻoe ke hoʻoponopono i ka ʻike nitrile i loko o HTBN e hoʻoponopono i ke kū'ē ʻana o ka solvent. ʻO nā pae acrylonitrile kiʻekiʻe e hoʻonui i ka polarity a hoʻonui i ke kū'ē ʻana i ka wahie. Eia nō naʻe, ʻo ke polarity kiʻekiʻe e hoʻonui pū i ka viscosity resin mua. Pono ʻoe e hoʻomehana i ka HTBN i 50°C i ka wā o ka degassing e hōʻemi i ka viscosity hana ma mua o ka hoʻokomo ʻana i kāu diisocyanate i koho ʻia.

Nā Kūlana Hoʻokumu Koʻikoʻi a me ka Hana ʻana

Nā Lākiō Stoichiometric a me ka Mana Kuhikuhi NCO

Pono ʻoe e kāohi pono i ka lakio stoichiometric ma waena o nā hui isocyanate ikaika a me nā hui hopena rubber. E kuhikuhi i kahi helu kuhikuhi NCO ma waena o 1.02 a me 1.08 e hōʻoia i ka crosslinking kemika piha. ʻO kahi helu kuhikuhi ma lalo o 1.00 e waiho i nā oligomers i pane ʻole ʻia. Hana kēia mau molekala manuahi ma ke ʻano he plasticizers makemake ʻole ʻia a hōʻemi i ka pono o ke kūkulu ʻana. I ka ʻaoʻao ʻē aʻe, ʻo kahi helu kuhikuhi ma luna o 1.10 ke kumu o ka crosslinking nui, kahi e hoʻolilo ai i kāu elastomer i hoʻōla ʻia i palupalu.

ʻO ke ʻano o ka ʻāpana a me ka hoʻokaʻawale ʻana o ka Microphase

Hoʻokele pololei ka hoʻokaʻawale ʻana o ka microphase i ka hana mechanical o kāu matrix polymer i hoʻōla ʻia. Hoʻokuke kūlohelohe nā iwi kuamoʻo rubber non-polar i nā ʻāpana paʻakikī urethane polar a i ʻole urea. Hiki iā ʻoe ke hoʻonohonoho i kēia incompatibility kemika e hoʻokele i ka ʻākoakoa ponoʻī i ka wā o ka hoʻōla ʻana. Hana nā ʻāpana paʻakikī i hoʻopuehu ʻia ma ke ʻano he crosslinks kino e hoʻoikaika i ka ikaika tensile. I kēia manawa, mālama nā ʻāpana palupalu rubber hoʻomau i ka maʻalahi o ka mahana haʻahaʻa a hoʻopili i ka ikehu hopena dynamic.

Ka Hoʻoponopono ʻana i ka Viscosity a me ka Hoʻonui ʻana i ka Pot-Life

I ka hoʻohālikelike ʻana i nā Isocyanates me nā Reactive Liquid Rubbers (nā ʻano HTPB, pinepine ka viscosity mua kiʻekiʻe keakea nei i ka hoʻopiha ʻana i ka ʻōpala a me ka degassing kūponoHoʻohaʻahaʻa nā mea hoʻoheheʻe non-reactive i ka viscosity, akā hana lākou i nā hakahaka nāwaliwali i ka wā e mahu ai. Akā, hana ka HTPB kaumaha molekala haʻahaʻa loa ma ke ʻano he mea hoʻoheheʻe reactive i nā ʻano polymer, e ʻae ana i ka hōʻemi ʻana i ka viscosity maikaʻi me ka mālama ʻana i nā waiwai mechanical a me ke kino o ka mea.

Manaʻo kōkua: E hoʻomehana i kāu laholio wai i 50°C ma mua o ka hoʻohui ʻana i ka mea hōʻola e hoʻolōʻihi i ke ola o ka ipu hao a wikiwiki i ka hoʻokuʻu ʻana o nā pehu.

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• E hoʻohālikelike i ka HTPB non-polar me MDI a i ʻole TDI e hoʻonui i ka hydrophobicity a me ka maʻalahi o ka mahana haʻahaʻa me ke kumukūʻai kūpono.
• E hoʻohui iā HTPB me ka aliphatic IPDI a i ʻole HDI no ke kūpaʻa UV kiʻekiʻe a me ke ola lōʻihi o ka pot-life.
• E hoʻohana i nā laholio nitrile (CTBN, ATBN, HTBN) i nā ʻōnaehana polar e hoʻoikaika i ka paʻakikī haki a me ke kūpaʻa ʻana i ka aila.
• E kāohi pono i ka stoichiometry NCO. ʻO nā lakio pololei e pale i nā oligomers i pane ʻole ʻia mai ka hoʻonāwaliwali ʻana i kāu elastomer.

Nā nīnau i nīnau pinepine ʻia

Pehea ʻoe e koho ai ma waena o MDI a me IPDI no nā ʻōnaehana HTPB?

Manaʻo kōkua wikiwiki: E hoʻohālikelike i kāu ʻano hoʻōla i ke kaiapuni o kāu noi.

E koho i ka MDI ke makemake ʻoe i ka ikaika tensile kiʻekiʻe a me ke kumukūʻai haʻahaʻa no nā noi o loko. E koho i ka IPDI no nā ʻano hana waho e pono ai ke kūpaʻa UV a me ke ola pot lōʻihi.

No ke aha ʻoe e mālama ai i kahi papa kuhikuhi NCO ma waena o 1.02 a me 1.08?

Hoʻopaʻa kēia lakio kikoʻī i ka crosslinking kemika piha. Kāohi ia i ka rubber wai i hana ʻole ʻia mai ka palupalu ʻana i kāu matrix a kāohi i ka crosslinking nui mai ka hana ʻana i kahi elastomer brittle.

Pehea e hoʻomaikaʻi ai ʻo CTBN i ka paʻakikī o ka haki i nā hybrids epoxy-polyurethane?

Hoʻopili ʻia ʻo CTBN i loko o nā ʻāpana laholio liʻiliʻi i ka wā e hoʻōla ai. Hoʻopili kēia mau ʻāpana laholio microscopic i ka ikehu hopena a hoʻōki i ka laha ʻana o ka māwae ma loko o kāu matrix polymer i hoʻōla ʻia.