Polyurethanes side-chain groups

In a systematic study on the adsorption of mixtures of associative thickeners of the polyurethane type and nonylphenol ethoxylates on a hydrophobic latex, it was demonstrated that polymers with hydrophobic side chains along the backbone could displace the nonionic surfactant provided that the concentration of polymer hydrophobe units was high enough. For associative thickeners with only terminal hydrophobic chains, it was found that the size of these chains is a decisive factor in competitive adsorption. In addition, the distance between the hydrophobic end-groups is of importance the shorter the distance, i.e. the higher the concentration of hydrophobic chains, then the more effective the polymer is in displacing the nonionic surfactant. 

PC J1 PC j t PC 1 (pc Figure 11.9 Segmented polyurethane with phosphorylchoUne group as side chain. 

In summary, there are two entropically driven processes for surface concentration of the P[3F-co-BrOx] soft block. 3F repeat units are surface concentrated by virtue of low surface energy, immiscibility, and side chain length that mimics an end-group. BrOx repeat units are miscible with the PTMO domain of the bulk phase and lack an end-group-like architecture. The latter provides a contravening effect that works against surface concentration in the chosen bulk polyurethane. 

In 1997, the same working group (Branger et al., 1997) published results with an azo-dye containing dimesitylboryl units used in the side chains in a polyurethane matrix (Scheme 13.2). The main... 

Figure 11.9 Segmented polyurethane with phosphorylcholine group as side chain.

C. A Side-Chain Polyurethane Based on Polysiloxanes with Pendant Primary Alcohol and Quaternary Ammonium Groups... 

Hazzi2a-Laskar et al. modified polysUoxane 62 to a polysiloxane that contained a primary alcohol and quaternary ammounium group 65 side chain. Polymer 65 was modified further to a siloxane-based side-chain polyurethane 66 (Scheme 24). This copolymer (3) had potential as a biocide. 

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