Organic silicon modified polymeric nonionic surfactant and preparation method thereof

The invention relates to the technical field of surfactant preparation, in particular to an organic silicon modified polymeric nonionic surfactant and a preparation method thereof. The method comprises the following steps: (1) preparing raw materials including isocyanate, fatty alcohol-polyoxyethylene ether, dihydroxyalkyl-terminated polysiloxane, a catalyst and a solvent; (2) mixing isocyanate with dihydroxyalkyl-terminated polysiloxane, fatty alcohol-polyoxyethylene ether, a catalyst and a solvent, and carrying out polymerization reaction, so as to prepare an organic silicon modified polymeric nonionic surfactant solution; and (3) removing the solvent in the organic silicon modified poly-type nonionic surfactant solution. According to the preparation method, the difunctional end dihydroxyalkyl polysiloxane with weak reactivity is firstly reacted with the HDI tripolymer to preferentially form a double-end-capped product which is uniform in structure and is opposite to the end dihydroxyalkyl polysiloxane by t