Study On The Synthesis And Properties Of Polyurethane Macromolecular Surfactants

Polymeric surfactants have the characteristics of large volume of single molecule, spaceshielding and electrostatic exclusion, with which consist of hydropHilic group andhydropHobic group whose molecular weight are about 10~4~10~6g/mol. They have been widelyinvestigated in nanomaterial synthesis and medicine delivery. Based on the synthesis ofaqueous polyurethane surfactants that have been existed in, it is the first time in this study thatcombined the cationic units and nonionic structure which has the resistance of acid andelectrolyte in polyurethane surfactants structure in domestic research. In view of widely easilychoosed and low cost raw materials, this subject targeted to prepare a series of water solublepolyurethane polymeric surfacents which containing oxyethylene(EO) units or quaternaryammonium salt as their hydropHilic group, and containing carbamate structure, methylcyclostructure, propylene oxide (PO) units as hydropHobic group. The properties such as watersolubility, surface activity, stability and emulsification performance have been investigated byexperimental methods, to offer mesoscale information for theoretical research and practicalapplication in the field of paints, inks, treatment of fabrics, emulsion polymerization and otherareas. The main results are summarized as follows:(1) Three kinds of cationic macromolecular polyurethane surfactants (denoted as YPUS)were synthesized with tolylene diisocyanate(TDI), polypropylene glycol (PPG) ,N-methyldiethanolamine(MDEA) as raw materials. The products were characterized by FTIR and GPC.It is shown that YPUS have good water-solubility ability, favorable surface performance, andemulsifying capacity of such surfactants was greatly outstanding. The surface tense ofYPUS-8 is 29 mN/m whose critical micelle concentration(CMC) is 3.16 g/L, which is best.(2) A series of water-borne nonionic polyurethane surfactants(denoted as FPUS) withcertain molecular were prepared by the tolylene diisocyanate(TDI), polypropylene glycol(PPG) and polyethylene glycols(PEG). Their structures were identified by FTIR and themolecular weight were confirmed by GPC. The effects of the length in hydropHobic groupand the number of EO units in hydropHilic group on their properties were studied. It isdiscovered that the number of EO units in hydropHilic group of FPUS ware mainlyinfluenced the surface activity. FPUS3 has the ability that the surface tension for 35.4 mN/m,whose CMC is 1 g/L.(3) Based on the viewpoint that synergistic effects and synergistic effect emerged whensurfactants were mixed, three types of cationic-nonionic polyurethane surfactants(denoted asYFPUS) were succesfully designed and obtained, which were characterized by FTIR andGPC. From the study on properties, it is shown that YFPUS has good water-solubilityability,favorable surface performance and emulsifying capacity, and the cloud pointtemperature are all above 90℃. YFPUS1 has the ability that the surface tension for 26.3mN/m, whose CMC is 4.5 g/L.Compared with the preparation for anionic polyurethane surfactants or nonionicpolyurethane surface active agents in other domestic research, the cationic-nonionicpolyurethane surfactants obtained in this study have excellent advantages on reducing thesurface tension, which the relative molecular mass are large.