Structure-Properties Relationship in Waterborne Poly(Urethane-Urea)s Synthesized with Dimethylolpropionic Acid (DMPA) Internal Emulsifier Added before, during and after Prepolymer Formation
| Autor: | Abbas Khoshnood, José Miguel Martín-Martínez, Mónica Fuensanta |
|---|---|
| Přispěvatelé: | Universidad de Alicante. Departamento de Química Inorgánica, Adhesión y Adhesivos |
| Rok vydání: | 2020 |
| Předmět: |
Thermogravimetric analysis
Materials science Thermal properties Polymers and Plastics Hard and soft segments Methyl ethyl ketone (MEK) prepolymer method Article structure–properties relationship lcsh:QD241-441 Viscosity waterborne poly(urethane-urea) Differential scanning calorimetry micro-phase separation lcsh:Organic chemistry Viscoelastic properties Thermal stability methyl ethyl ketone (MEK) prepolymer method hard and soft segments Thermal analysis Prepolymer Dimethylolpropionic acid (DMPA) Química Inorgánica Structure–properties relationship thermal properties dimethylolpropionic acid (DMPA) viscoelastic properties General Chemistry Dynamic mechanical analysis Waterborne poly(urethane-urea) Micro-phase separation adhesion Chemical engineering Adhesion Particle size |
| Zdroj: | Polymers Polymers, Vol 12, Iss 2478, p 2478 (2020) Volume 12 Issue 11 RUA. Repositorio Institucional de la Universidad de Alicante Universidad de Alicante (UA) |
| ISSN: | 2073-4360 |
| Popis: | Dimethylolpropionic acid (DMPA) internal emulsifier has been added before, during and after prepolymer formation in the synthesis of waterborne poly(urethane-urea)s (PUDs) and their structure–properties relationships have been assessed. PUDs were characterized by pH, viscosity and particle size measurements, and the structure of the poly(urethane-urea) (PU) films was assessed by infra-red spectroscopy, differential scanning calorimetry, X-ray diffraction, thermal gravimetric analysis, plate–plate rheology and dynamic mechanical thermal analysis. The adhesion properties of the PUDs were measured by cross-hatch adhesion and T-peel test. The lowest pH value and the highest mean particle size were found in the PUD made by adding DMPA after prepolymer formation, all PUDs showed relatively ample mono-modal particle size distributions. The highest viscosity and noticeable shear thinning were obtained in the PUD made by adding DMPA during prepolymer formation. Depending on the stage of addition of DMPA, the length of the prepolymer varied and the PU films showed different degree of micro-phase separation. Because the shortest prepolymer was formed in the PU made with DMPA added before prepolymer, this PU film showed the lowest storage moduli and early melting indicating higher degree of micro-phase separation. The highest storage modulus, later melting, higher temperature and lower modulus at the cross between the storage and loss moduli corresponded to the PU made by adding DMPA after prepolymer formation, because the longer prepolymer produced during synthesis. The lowest thermal stability corresponded to the PU made by adding DMPA during prepolymer formation and the structures of all PU films were dominated by the soft domains, the main structural differences derived from the hard domains. Whereas DMPA-isophorone diisocyanate (IPDI) urethane and urea hard domains were created in the PU film made by adding DMPA during prepolymer formation, the other PU films showed DMPA-IPDI, polyester-IPDI and two different DMPA-IPDI-polyester hard domains. Finally, the adhesion properties of the PUDs and PU coatings were excellent and they were not influenced by the structural differences caused by adding DMPA in different stages of the synthesis. |
| Databáze: | OpenAIRE |
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