Síntese e caracterização de dispersões aquosas de poliuretanos à base de copolímeros em bloco de poli(glicol etilênico) e poli(glicol propilênico) Synthesis and characterization of polyurethane aquous dispersions based on poly(ethylene glycol) and poly(propylene glycol) block copolymers

• Main Authors: Fernanda M. B. Coutinho, Marcia C. Delpech, Cristiane C. Santos, Rosiléa B. L. Almeida
• Format: Article
• Language: English
• Published: Sociedade Brasileira de Química 2008-01-01
• Series: Química Nova
• Subjects: polyurethane; aqueous dispersions; non-polluting systems
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422008000600030
• ISSN: 0100-4042; 1678-7064

<abstract language="eng">Non-polluting polyurethane aqueous dispersions, with 40% of solids content, were synthesized based on block copolymers of poly(ethylene glycol) and poly(propylene glycol) (PEG-b-PPG), with PEG hydrophilic segments content of 7 and 25%, poly(propylene glycol) (PPG), dimethylolpropionic acid (DMPA), isophorone diisocyanate (IPDI), and hydrazine. Different formulations were synthesized by varying the equivalent-grams ratios between isocyanate and hydroxyl groups (NCO/OH) and PPG and (PEG-b-PPG). The presence of high amounts of PEG in the formulations provoked the formation of gels. Average particle size and viscosity of the dispersions were determined. Mechanical properties and water absorption resistance of cast films were evaluated.