1. Kodi Mungasankhe Bwanji Dicarboxylic Acids Kuti Mupange Polyester Polyol Formulation?

Mafuta Onunkhira: Kukonza Kulimba ndi Kukana Kutentha

Isophthalic Acid (IPA) ndi Terephthalic Acid (PTA)

Ma dicarboxylic acid onunkhira amagwiritsidwa ntchito kwambiri pokonza:

Asidi ya Terephthalic (PTA)Ili ndi kapangidwe kolunjika bwino komanso kachulukidwe kamphamvu ka makristalo.

Pamene PTA ichitapo kanthu ndi ma diol afupiafupi monga ethylene glycol (EG) kapena 1,4-butanediol (BDO), kapangidwe ka polyester komwe kamachokerako kangasonyeze khalidwe lamphamvu la crystallization, zomwe zimapangitsa polyester polyol kukhala ngati sera kapena yolimba kutentha kwa chipinda.

Izi zitha kuchepetsa:

• ✖Kusinthasintha kwa zinthu
• ✖Kukhazikika kwa malo osungira
• ✖Kugwiritsa ntchito mosavuta

Chifukwa chake, ma polyester polyols oyera ochokera ku PTA sagwiritsidwa ntchito kawirikawiri paokha m'njira zothandiza.

Asidi ya Isophthalic (IPA)Ili ndi kapangidwe ka molekyulu kosagwirizana pang'ono chifukwa magulu awiri a carboxyl ali pamalo a meta. Izi zimachepetsa chizolowezi cha crystallization ndikuwonjezera kukhazikika kwa madzi.

Ma polyester polyols okhala ndi IPA nthawi zambiri amapereka:

• ✔Tg Yapamwamba
• ✔Kuwonekera bwino
• ✔Kuyenda bwino kwa madzi

Mu ma formula ambiri a mafakitale, IPA imayambitsidwa pamodzi ndi PTA kapena aliphatic acids kuti igwirizane bwino ndi kusinthasintha.

Aliphatic Acids: Kuwonjezeka kwa Kusinthasintha

Asidi ya Adipic (AA)

Adipic acid ndi imodzi mwa ma aliphatic dicarboxylic acid omwe amagwiritsidwa ntchito kwambiri popanga polyol polyol.

Unyolo wake wosinthasintha wa kaboni zisanu ndi chimodzi umapereka:

• •Kusinthasintha kwa kutentha kochepa
• •Kutanuka kwabwino
• •Kuchepetsa Tg

Ma polyester polyols okhala ndi Adipic acid nthawi zambiri amakhala ndi Tg values ​​​​pafupifupi-60°C mpaka -40°C, kutengera kapangidwe ka mamolekyu.

Kapangidwe kameneka kamathandizira:

• •Mphamvu yayikulu yokoka
• •Kukana bwino kukanda
• •Ntchito yabwino kwambiri yamakina

Sebacic Acid (SA)

Sebacic acid ili ndi unyolo wautali wa kaboni kuposa adipic acid.

Ubwino:

• ✔Kusinthasintha kwakukulu
• ✔Kuchita bwino kwa kutentha kotsika
• ✔Makhalidwe abwino a hydrophobic

Komabe, chifukwa cha mtengo wake wokwera, SA imagwiritsidwa ntchito makamaka pa ntchito zapamwamba za polyurethane komwe kumafunika kukana kuzizira kwambiri.

Zigawo Zogwira Ntchito za Asidi: Dimer Acid ndi Phthalic Anhydride

Dimer Acid

Dimer acid imayambitsa izi:

• •Maunyolo aatali osinthasintha a molekyulu
• •Katundu woopsa ndi madzi
• •Kusinthasintha kwabwino
• •Kukana bwino kwa hydrolysis

Komabe, kuwonjezeka kwa dimer acid kungachepetse Tg ndi kuuma. Kawirikawiri imaganiziridwa kuti ndi njira za polyurethane zomwe zimafuna kusinthasintha komanso kukana chinyezi.

Phthalic Anhydride (PA)

Phthalic anhydride ndi gawo lonunkhira lotsika mtengo komanso lothandiza kwambiri pochita zinthu.

Zingathe kusintha:

• ✔Kuuma
• ✔Kulimba
• ✔Mpikisano pamitengo

Komabe, chifukwa cha zotsatira zake za steric, reactivity yake ya gulu lotsiriza ndi yotsika poyerekeza ndi IPA.

Njira Yachizolowezi Yopangira Asidi

Njira yodziwika bwino yopangira polyester polyol ndi iyi:

• •Mafuta onunkhira: amapereka kuuma ndi mphamvu
• •Aliphatic acids: amapereka kusinthasintha ndi kulimba

Chiŵerengero chenicheni chiyenera kusinthidwa nthawi zonse malinga ndi momwe chikugwiritsidwira ntchito.

2. Kodi Mungasankhe Bwanji Ma Diol a Kapangidwe ka Polyel Polyol?

Ethylene Glycol (EG)

Ethylene glycol ndi diol yosavuta kwambiri yomwe imagwiritsidwa ntchito mu chemistry ya polyester.

Chifukwa cha kapangidwe kake kafupika ka mamolekyu, EG imapereka:

• •Kukhazikika kwa unyolo wambiri
• •Chizolowezi champhamvu cha crystallization

Akaphatikizidwa ndi PTA, EG imatha kupanga mapangidwe ofanana ndi PET, zomwe zingayambitse polyester polyols kukhala olimba kutentha kwa chipinda. Chifukwa chake, polyester polyols yoyera yochokera ku EG si yachilendo.

Mu njira zothandiza, EG nthawi zambiri imaphatikizidwa ndi:

kusintha momwe zinthu zilili komanso momwe zinthu zimagwirira ntchito.

Ubwino umodzi wofunikira wa EG ndi:

• ✔Mtengo wotsika
• ✔Kupezeka kwakukulu

Pakupanga polyol ya polyol pogwiritsa ntchito zipangizo za PET zobwezerezedwanso, EG ikadali chinthu chofunikira kwambiri.

Diethylene Glycol (DEG)

DEG imayambitsa ma ether bond mu unyolo wa polyester.

Kulumikizana kwa ether kosinthasintha kumapereka:

• •Lower Tg
• •Kuchepa kwa kukhuthala
• •Kuyenda bwino kwa kayendedwe ka madzi

Ma polyester polyols ochokera ku DEG amagwiritsidwa ntchito kwambiri pamene kukonza kusinthasintha ndikofunikira.

Komabe, ma ether bond angakhale ndi kukana kochepa ku kutentha kwa nthawi yayitali. Chifukwa chake, machitidwe a DEG nthawi zambiri amaphatikizidwa ndi ma diol okhazikika monga NPG.

Neopentyl Glycol (NPG)

NPG ili ndi kapangidwe ka kaboni ka quaternary komwe kali ndi magulu awiri a methyl.

Kapangidwe kapadera aka kamaletsa kuyenda kwa mamolekyu ndipo kamapereka:

• •Tg Yapamwamba
• •Kukhazikika kwabwino kwambiri kwa kutentha
• •Kukana kwabwino kwa nyengo
• •Kulimbitsa kukana kwa hydrolysis

Chifukwa cha kulimba kwake kwabwino, NPG imagwiritsidwa ntchito kwambiri mu:

• •Zophimba za PU
• •Ntchito zakunja
• •Makina a polyurethane osagwedezeka ndi nyengo

1,4-Butanediol (BDO)

1,4-Butanediol ndi imodzi mwa ma diol ofunikira kwambiri omwe amagwiritsidwa ntchito mu polyurethane elastomer ndi TPU.

Kapangidwe kake ka mzere wa kaboni anayi kamapereka:

• •Kukhazikika bwino kwa unyolo
• •Kugwirizana kwamphamvu pakati pa mamolekyulu
• •Katundu wabwino kwambiri wamakina

Akaphatikizidwa ndi aromatic acids monga PTA, BDO imatha kupanga magawo a crystalline okonzedwa bwino ofanana ndi mapangidwe a PBT.

Izi zimathandiza kuti:

• ✔Mphamvu yayikulu yokoka
• ✔Kukana bwino kukanda
• ✔Kulumikizana kwabwino kwa thupi

Komabe, kuchuluka kwa BDO kungapangitse kuti ma crystallization achuluke, zomwe zimapangitsa kuti ma polyester polyols akhale olimba kapena okhuthala kutentha kwa chipinda.

Pofuna kukonza magwiridwe antchito, BDO nthawi zambiri imaphatikizidwa ndi:

kuchepetsa kupangika kwa kristalo kwambiri pamene mukusunga mphamvu zamakanika.

Trimethylolpropane (TMP): Kuyambitsa Kulamulira kwa Ma Branchi

Trimethylolpropane (TMP) ndi mowa wogwiritsidwa ntchito m'njira zambiri wokhala ndi magulu atatu a hydroxyl. Mosiyana ndi ma diol wamba, TMP imayambitsa mapangidwe a nthambi mu polyols ya polyester.

Kuchuluka pang'ono kwa TMP kumatha kuwonjezeka:

• •Kugawikana kwa maselo
• •Kuchulukana kwa Crosslink
• •Kuuma komaliza kwa polyurethane

TMP imagwiritsidwa ntchito kwambiri popanga:

• •Zophimba za polyurethane zogwira ntchito bwino
• •Machitidwe olimba a PU
• •Ma prepolymer a polyurethane opangidwa ndi nthambi

Mu mitundu yambiri ya mankhwala, kuchuluka kwa TMP kumayendetsedwa mosamala chifukwa nthambi zambiri zimatha kuwonjezera kukhuthala kwa thupi ndikuchepetsa kuthekera kokonza.

3. Kodi Mungasinthe Bwanji Chiŵerengero cha Mowa ndi Asidi mu Polyester Polyol Formulation?

Chiŵerengero Chochuluka cha Mowa

Mu kapangidwe ka polyol ya polyol, zigawo za mowa nthawi zambiri zimagwiritsidwa ntchito mopitirira muyeso kuti zipange mapangidwe otsirizidwa ndi hydroxyl.

Pa polyols zolemera zochepa za polyester, chiŵerengero cha mowa wochuluka chikhoza kuwonjezeredwa kufika pa:1.8–2.0: 1

Ma hydroxyl apamwamba amapereka magulu a hydroxyl omwe amagwira ntchito bwino popanga polyurethane.

Komabe, kumwa mowa mopitirira muyeso kungachepetse kulemera kwa maselo ndipo kungakhudze moyipa:

Chifukwa chake, chiŵerengero cha mowa ndi asidi chiyenera kukonzedwa bwino malinga ndi momwe polyurethane imagwiritsidwira ntchito komaliza.

Ubale Pakati pa Chiŵerengero cha Mowa ndi Mtengo wa Asidi

Pakapangidwa polyol, madzi opangidwa amachotsedwa nthawi zonse kuti apititse patsogolo esterification ndi condensation reactions.

Ngati mowa wochuluka sukwanira:

• •Kuchuluka kwa asidi kumakhalabe kwakukulu
• •Kuchitapo kanthu kumakhala kochedwa
• •Kuchuluka kwa asidi komaliza kumakhala kovuta kuchepetsa

Asidi wochepa ndi wofunikira chifukwa ma asidi otsala angakhudze momwe polyurethane imagwirira ntchito. Pamene polyester polyol imagwira ntchito ndi isocyanates, chinyezi chotsalira ndi zigawo za asidi zingathandize:

Pa ntchito zambiri za polyurethane, kuwongolera kuchuluka kwa asidi pansipa:1 mg KOH/gndi cholinga chofunikira kwambiri.

4. Momwe MungasankhireZothandiziraKupanga Polyol?

Kusankha pakati pa TBT ndi BTO kumadalira:

5. Kuwongolera Njira Zopangira Polyol

Magawo akuluakulu akuphatikizapo:

1. Kukhazikika kwa Ester
2. Kuchuluka kwa madzi m'thupi
3. Kufunika kwa Hydroxyl ndi kusintha kwa kufunika kwa asidi

Gawo 1: Gawo la Esterification

Pa nthawi ya esterification, zinthu zotsatirazi zimayikidwa mu reactor:

Kawirikawiri zimachitika pa:180°C

Madzi opangidwa kuchokera ku esterification amachotsedwa kudzera mu:

• •Kuchotsa nayitrogeni
• •Machitidwe a Condenser

Kupita patsogolo kwa zomwe zimachitika kungayang'aniridwe kudzera mu:

• •Kuchuluka kwa madzi omwe asonkhanitsidwa
• •Kuyesa kwa asidi

Gawo 2: Gawo la Polycondensation

Pambuyo pa esterification, dongosololi limalowa mu gawo la polycondensation.

Mikhalidwe yachizolowezi:

• •Kutentha:200–220°C
• •Kupanikizika kochepa: ntchito ya vacuum

Vacuum imathandiza kuchotsa madzi otsala ndi mowa wochuluka, zomwe zimapangitsa kuti mamolekyu achuluke.

Komabe, kutentha kwambiri kapena nthawi yayitali yochitira zinthu kungayambitse zotsatira zoyipa, kuwonjezeka kwa mtundu, komanso kuwonongeka kwa polima. Chifukwa chake, mikhalidwe ya zochitika iyenera kulamulidwa mosamala.

Gawo 3: Kulamulira Malo Othera

Mosiyana ndi PET polymerization, kupanga polyol ya polyol sikufuna kukula kwa molekyulu yolemera kwambiri. Zizindikiro zazikulu za khalidwe ndi izi:

Cholinga chofanana cha mafakitale:Mtengo wa asidi<1 mg KOH/gmusanatulutse.

Kusakwanira kwa vacuum ndi chimodzi mwa zifukwa zazikulu za izi:

• ✖Chinyezi chotsalira kwambiri
• ✖Asidi wokwera kwambiri
• ✖Kugwira ntchito koipa kwa polyurethane

6. Chidule cha Kapangidwe ka Polyester Polyol

Zinthu Zokhudza Kapangidwe	Zosintha Zofunikira	Mfundo Yosankha	Mtundu Wamba
Kulimba kwa msana	IPA, PTA, AA, SA	Ma asidi onunkhira amathandiza kukhazikika; ma asidi a aliphatic amapangitsa kusinthasintha	IPA/AA ≈ 7:3
Kusintha kwa Tg	EG, DEG, NPG, BDO	EG imawonjezera kristalo; DEG imachepetsa kukhuthala; NPG imakulitsa kulimba; BDO ​​imakulitsa mphamvu	Kutengera ndi ntchito
Kulamulira kulemera kwa maselo	Chiŵerengero cha mowa ndi asidi	Kuchuluka kwa mowa kumapangitsa kuti zinthu zomwe zimachotsedwa ndi hydroxyl ziwonongeke.	Mowa/Asidi = 1.3
Kusankha kwa Catalyst	TBT motsutsana ndi BTO	TBT yothandiza kuchitapo kanthu mwachangu; BTO yothandiza kuti hydrolysis ikhale yolimba bwino	BTO 0.2–0.5‰
Kulamulira nthambi	TMP/Glycerol	Zowonjezera zazing'ono zimathandizira kuchulukana kwa ma crosslink	TMP ≤3 mol%

7. Kodi Kapangidwe ka Polyel Polyol kamakhudza bwanji magwiridwe antchito a Polyurethane?

Kugwiritsa ntchito	Kapangidwe Koyenera ka Polyester Polyol
Ma PU Aluminiyamu	Ma polyol a polyester osinthika okhala ndi AA kuti azigwirana mwamphamvu komanso kulimba
Zophimba za PU	Machitidwe a IPA/NPG oteteza kuuma ndi kukana nyengo
Ma Elastomer a TPU	Machitidwe a AA + BDO a mphamvu yamakina ndi kukana kukwawa
PU Yoyendetsedwa ndi Madzi	Ma polyol a polyester osagwira hydrolysis okhala ndi makina othandizira okonzedwa bwino
Chikopa Chopangidwa	Polyester polyols yosinthasintha yokhala ndi kufewa kolamulidwa

Zofunikira pakugwiritsa ntchito → Zolinga za magwiridwe antchito → Kusankha monomer → Kapangidwe ka kapangidwe ka molekyulu → Kusankha Catalyst → Kukonza njira