Kev ua siab ntev
Polyether-raws li polyurethanes feem ntau pom muaj siab dua rebound (resilience) piv rau lawv cov polyester-based counterparts.
Dynamic thiab Mechanical Properties
Nyob rau hauv daim ntawv thov xav tau cov khoom uas muaj zog tensile ntau dua thiab txiav thiab tsim kua muag kuj, polyesters yog cov nyiam polyols. Polyethers impart qis hysteresis los yog kub buildup, uas ua rau lawv nyiam cov khoom siv dynamic xws li log, casters thiab rollers.
Abrasion Resistance
Abrasion hnav feem ntau yog tshwm sim los ntawm kev sib xyaw ntawm zawv zawg thiab impingement abrasion. Muaj ntau qhov kev ntsuam xyuas kev puas tsuaj uas tsim los ua kom pom tseeb ntawm cov khoom siv kev pabcuam, vim muaj ntau yam sib txawv tuaj yeem cuam tshuam kev ua haujlwm ntawm cov urethane elastomers. Xaiv qhov kev ntsuam xyuas kev puas tsuaj, uas yuav zoo sib xws nrog daim ntawv thov siv kawg, tuaj yeem yog qhov nyuaj heev.
Polyether-raws li polyurethanes, vim lawv cov kev ua haujlwm siab dua, muab kev ua haujlwm zoo dua hauv cov ntawv thov uas cuam tshuam kev puas tsuaj yog qhov tseem ceeb ntawm kev hnav. Qhov kev ua tau zoo no yog qhov tseeb tshwj xeeb rau PTMEG raws li elastomers.
Hauv kev nkag siab dav dav, qhov siab dua tensile thiab kua muag tsis kam ntawm cov ntaub ntawv polyester-based polyurethane muab qhov zoo dua hauv cov ntawv thov uas zawv zawg yog qhov tseem ceeb ntawm kev puas tsuaj.
Ib puag ncig uas cov khoom yuav tsum tau ua yuav tsum tau txiav txim siab. Lub peev xwm rau hydrolysis ntawm qhov chaw ntawm ester-based polyurethanes, piv txwv li, yuav cuam tshuam tsis zoo rau lawv lub sijhawm ntev ua haujlwm.
Cov yam ntxwv ua
PTMEG polyols yog lub luag haujlwm tseem ceeb hauv thawj diols nthuav qhia ntau yam tseem ceeb rau kev ua haujlwm. PTMEG polyols pom muaj qib qis heev ntawm acidity. Lawv cov ntsiab lus melting ntsuas nyob rau hauv chav tsev kub rau cov qib molecular yuag qis, xws li PTMEG 650. Cov qib molecular hnyav dua cov qib yaj me ntsis saum chav tsev kub, thiab lawv pom cov viscosity qis dua vim lawv qhov hnyav molecular faib yog nqaim. Tsis tas li ntawd, PTMEG polyols txhawb kev sib xws hauv kev tsim cov polyurethanes.
PPG polyols tsis yog qhov ua tau zoo thiab muaj qib ntawm mono-functionality. Lawv kuj muaj lwm yam hydroxyl moieties uas qis dua nyob rau hauv reactivity. Raws li, lawv qhov hnyav molecular faib thiab viscosity siab dua PTMEG raws li polyurethanes, thiab qhov hnyav molecular ua tiav feem ntau qis dua.
Thaum kawg, polyester polyols tuaj yeem muaj cov ntsiab lus melting siab thiab siab dua qib ntawm acidity, uas cuam tshuam rau catalyst reactivity. Cov polyols no nthuav dav qhov hnyav molecular faib thiab viscosities.