Editing Polyurethane (section)

===Catalysts===
{{main|catalyst}}
Polyurethane [[catalyst]]s can be classified into two broad categories, basic and acidic [[amine]]. [[Tertiary amine]] catalysts function by enhancing the nucleophilicity of the diol component. Alkyl tin carboxylates, oxides and mercaptides oxides function as mild Lewis acids in accelerating the formation of polyurethane. As bases, traditional amine catalysts include triethylenediamine (TEDA, also called [[DABCO]], 1,4-diazabicyclo[2.2.2]octane), [[dimethylcyclohexylamine]] (DMCHA), [[dimethylethanolamine]] (DMEA), [[Dimethylaminoethoxyethanol]] and bis-(2-dimethylaminoethyl)ether, a blowing catalyst also called A-99. A typical Lewis acidic catalyst is [[dibutyltin dilaurate]]. The process is highly sensitive to the nature of the catalyst and is also known to be [[autocatalytic]].<ref>{{Ullmann |doi=10.1002/14356007.a21_665.pub2 |title=Polyurethanes |year=2005 |last1=Adam |first1=Norbert |last2=Avar |first2=Geza |last3=Blankenheim |first3=Herbert |last4=Friederichs |first4=Wolfgang |last5=Giersig |first5=Manfred |last6=Weigand |first6=Eckehard |last7=Halfmann |first7=Michael |last8=Wittbecker |first8=Friedrich-Wilhelm |last9=Larimer |first9=Donald-Richard |last10=Maier |first10=Udo |last11=Meyer-Ahrens |first11=Sven |last12=Noble |first12=Karl-Ludwig |last13=Wussow |first13=Hans-Georg |isbn=978-3-527-30673-2 }}</ref>

Another class of catalysts was published in a study in May 2024. In this study, polyurethane synthesis was investigated in the presence of acid catalysts, namely [[dimethylphosphite]] (DMHP), [[methanesulfonic acid]] (MSA), and [[trifluoromethanesulfonic acid]] (TFMSA). The thermodynamic profile was examined and described in detail through computational tools, showing that TFMSA had the best catalytic properties. The study aimed to open the door to a new class of catalysts.<ref name= "Urethane Synthesis in the Presence of Organic Acid Catalysts—A Computational Study"> {{Cite journal|title=Urethane Synthesis in the Presence of Organic Acid Catalysts—A Computational Study|date=2024 |pmc=11123846 |language=en |last1=Waleed |first1=H. Q. |last2=Viskolcz |first2=B. |last3=Fiser |first3=B. |journal=Molecules (Basel, Switzerland) |volume=29 |issue=10 |page=2375 |doi=10.3390/molecules29102375 |doi-access=free |pmid=38792235 }}</ref>


Factors affecting catalyst selection include balancing three reactions: urethane (polyol+isocyanate, or gel) formation, the urea (water+isocyanate, or "blow") formation, or the isocyanate trimerization reaction (e.g., using potassium acetate, to form [[isocyanurate]] rings). A variety of specialized catalysts have been developed.<ref>{{cite web | title = Jeffcat Amine Catalysts for the Polyurethane Industry | year = 2006 | url = http://www.huntsman.com/performance_products/Media/JEFFCAT_Catalyst_Trifold_bulletin.pdf | access-date = 2007-10-23 |archive-url = https://web.archive.org/web/20071129082418/http://www.huntsman.com/performance_products/Media/JEFFCAT_Catalyst_Trifold_bulletin.pdf <!-- Bot retrieved archive --> |archive-date = 2007-11-29}}</ref><ref>{{cite web | title = Building quality with Air Products trimerisation catalysts | year = 2003 | url = http://www.airproducts.com/NR/rdonlyres/55C5A72A-D126-4888-9E1A-D24EFBE4AAC1/0/14004004EU.pdf | access-date = 2007-10-23 | archive-date = 2007-11-29 | archive-url = https://web.archive.org/web/20071129082418/http://www.airproducts.com/NR/rdonlyres/55C5A72A-D126-4888-9E1A-D24EFBE4AAC1/0/14004004EU.pdf | url-status = dead }}</ref><ref>{{Cite journal | title = FOMREZ Specialty Tin Catalysts for Polyurethane Applications | journal = 120-074-10 | date = January 2001}}</ref>