Carboxylic hydrophilic sarkar extenders DMBA da DMPA.

Gabatarwa

A cikin samar da polyurethane na ruwa, carboxylic acid a matsayin anionic hydrophilic sarkar extender wani nau'i ne na carboxylic acid tare da diol, wanda aka yi amfani da shi sosai don tsarin kwayoyin halitta na musamman da kyakkyawan aikin samfurin.
Carboxylic acid irin sarkar extender yafi hada da 2,2-dihydroxymethylpropionic acid (DMPA) da 2,2-dihydroxymethylbutyric acid (DMBA).Yana da na musamman multifunctional katange diol kwayoyin tare da biyu hydroxyl da carboxyl kungiyoyin.Bayan neutralization tare da alkali, free acid kungiyar iya rayayye inganta ruwa solubility ko watsawa yi na guduro;An gabatar da ƙungiyoyin polar don inganta mannewa na sutura da kayan rini na fibers na roba;Ƙara alkali solubility na shafi.Ana iya amfani da shi zuwa tsarin polyurethane mai narkewa, ruwa mai narkewa alkyd guduro da polyester guduro, epoxy ester shafi, polyurethane elastomer da foda shafi.
Hakanan za'a iya amfani dashi a cikin kayan sinadarai na fata, lu'ulu'u na ruwa, tawada, abubuwan abinci da ƙari na sinadarai, musamman a cikin kera emulsion polyurethane na ruwa da abubuwan gamawa na fata.Ba kawai mai sarkar sarkar ba ne, amma har ma mai kyau wakili mai emulsifying don polyurethane, wanda zai iya inganta zaman lafiyar ruwan shafan ruwa na polyurethane, don haka ana amfani dashi sosai.

Fa'idodin Amfani da Dihydroxymethyl Carboxylic Acid

Ruwan shafawa na polyurethane mai ruwa-ruwa yawanci yana gabatar da wakili na hydrophilic cikin sarkar polyurethane, sannan a cire shi da alkali don samar da gishiri, kuma ya watse a cikin ruwan da ba shi da ruwa ta hanyar motsa jiki don samar da ruwan shafa mai ruwa na polyurethane.
Akwai nau'ikan nau'ikan nau'ikan nau'ikan hydrophilic guda uku da ake amfani da su a cikin polyurethane na ruwa: anionic, cationic da wadanda ba ionic ba.Nau'in anionic yafi hada da: 2,2-dihydroxymethylpropionic acid, 2,2-dihydroxymethylbutyric acid, tartaric acid, butanediol sulfonate, sodium ethylenediamineethanesulfonate, glycerol da maleic anhydride;Nau'in cationic ya haɗa da: methyldiethanolamine, triethanolamine, da dai sauransu;Nau'in da ba na ionic ba ya haɗa da hydroxyl ƙarewar polyethylene oxide.
Abubuwan da ba na ion hydrophilic wakili ba kamar polyethylene oxide dole ne ya kasance mai girma sosai don sanya tarwatsawar ta tsaya.Ruwan ruwa na polyurethane na ruwa wanda aka yi da hydroxyl polyoxyethylene ether a matsayin ƙungiyar hydrophilic yana da juriya mai kyau na electrolyte, amma juriya na ruwa na fim din yana da talauci sosai, don haka ba shi da amfani;
Cationic hydrophilic wakili, kamar ethylenediamine sodium acrylate adduct, a matsayin hydrophilic fili, sa dukan dauki tsarin alkaline.Akwai ba kawai saurin amsawa tsakanin - ƙungiyar NH2 da - ƙungiyar NCO ba, har ma da martani tsakanin - ƙungiyar NCO da - nhcoo.Sabili da haka, halayen yana da wuyar sarrafawa kuma yana da sauƙin gel.Bugu da ƙari, ruwan shafa mai da aka shirya yana da ƙananan barbashi da ƙarancin juriya na fim, don haka ba za a iya amfani da shi a masana'antu ba;
Dihydroxymethyl carboxylic acid a cikin nau'in anionic ya ƙunshi ƙungiyoyin hydroxyl guda biyu kuma yana aiki azaman mai shimfiɗa sarkar.Wannan rawar dual yana sa ya nuna babban fa'ida a cikin shirye-shiryen emulsifying Pu lotion.A lokacin da ake kira carbamate, yana sa tsarin amsawa ya zama acidic.A karkashin yanayin acidic, halayen tsakanin - NCO da - Oh yana da sauƙi, yayin da - nhcoo - baya shiga cikin amsawa kuma ba zai haifar da gel ba.Bugu da kari, dimethylol carboxylic acid shima yana aiki a matsayin mai sarkar sarkar, don haka kungiyar hydrophilic (watau kungiyar carboxyl) tana cikin sashin sarkar macromolecular.Yin amfani da amine na uku azaman wakili na tsaka-tsaki, za a iya shirya resin polyurethane mai ruwa tare da kyakkyawan kwanciyar hankali da ingantaccen ruwa mai samar da fim da juriya mai ƙarfi.Dihydroxymethyl carboxylic acid shine mafi kyawun fili na hydrophilic wanda ake amfani dashi sosai a cikin shirye-shiryen guduro na polyurethane na ruwa.

2,2-Dihydroxymethylpropionic Acid (DMPA) da 2,2-Dihydroxymethylbutyric Acid (DMBA)

Daga cikin nau'ikan nau'ikan nau'ikan nau'ikan Dihydroxymethyl carboxylic acid, 2,2-dihydroxymethyl propionic acid an daɗe ana amfani da shi kuma shine sarƙar sarkar hydrophilic wanda ake amfani dashi sosai a halin yanzu.Duk da cewa yana da fa'idodi da yawa, amma yana da illoli da yawa, musamman saboda yanayin narkewar da yake da shi (180-185 ℃), wanda ke da wuyar zafi da narke, wanda ke buƙatar ƙara wasu kaushi mai ƙarfi kamar N-methylpyrrolidone (NMP). n N-dimethylamide (DMF), acetone, da dai sauransu, yayin da NMP yana da babban wurin tafasa, wanda ke da wuya a cire bayan shirya APU.Bugu da ƙari, DMPA yana da ƙananan solubility a cikin acetone, kuma babban adadin acetone yana buƙatar ƙarawa a cikin tsarin haɗin gwiwa.Tsarin cirewar ketone ba wai kawai yana lalata makamashi ba har ma yana kawo haɗarin aminci.Saboda haka, yin amfani da 2,2-dihydroxymethylpropionic acid ba kawai mai girma a cikin amfani da makamashi ba, amma kuma yana da sauƙi don haifar da ragowar kwayoyin halitta a cikin samfurin.
Idan aka kwatanta da 2,2-dihydroxymethyl propionic acid, 2,2-dihydroxymethyl butyric acid yana da fa'idodi masu zuwa:
1. Yana da mafi kyau solubility a cikin kwayoyin kaushi.Tebur mai zuwa yana nuna bayanan solubility na DMBA da DMPA a cikin yanayi daban-daban da kaushi;
Bayanan narkewa na DMBA da DMPA a cikin yanayi daban-daban da kaushi:

Solubility: naúrar: g/100g sauran ƙarfi
Solubility a cikin ruwa: 48% don DMBA da 12% don DMPA.

2. High dauki kudi, sauri dauki gudun da low dauki zazzabi.Misali, lokacin amsawa don haɗar polyurethane prepolymer gajere ne, gabaɗaya kawai mintuna 50-60, yayin da DMPA yana ɗaukar mintuna 150-180;
3. Ana amfani da ruwan shafa na polyurethane na ruwa tare da ƙananan ƙwayar ƙwayar cuta da kunkuntar rarraba;
4. Ƙananan narkewa, 108-114 ℃;
5. Bambance-bambancen nau'o'in na iya rage yawan amfani da abubuwan da ake amfani da su, don haka rage farashin kaushi da zubar da maganin ruwa;
6. Ana iya amfani dashi don shirya tsarin tsarin polyurethane da polyester gaba daya mara ƙarfi;
A cikin ainihin tsarin kira, baya buƙatar cinye kowane sauran ƙarfi.Ruwan ruwan shafa da aka samar yana da kyakkyawan aiki da kyawawan kayan aikin injiniya na fim, wanda ba wai kawai ya rage lokacin amsawa ba, yana rage yawan amfani da makamashi, amma kuma yana adana makamashi.Sabili da haka, 2,2-dihydroxymethyl butyric acid shine sanannen fili na hydrophilic.