This assumption received support that is described in detail in [26]. As it was reported [26, 27], the average conformation of grafted PAA chains is controlled by the grafting ratio: for D70-g-PAA20, it is close to that of a worm-like chain; for D70-g-PAA5, it differs from that of a worm-like chain, although it is definitely not random, namely, the PAA-grafted chains are highly extended near their tethering point and recover a random conformation far from this point. The number of grafted chains and their average conformation are closely related to the compactness of the branched macromolecules which can be assessed through the

buy AG-881 ratio R z 2 /M w [27] (see Table 1). When the ratio R z 2 /M w is lower, the compactness is higher. Table 1 Molecular parameters of the D70- g -PAA copolymers and the LY333531 manufacturer linear PAA Sample M w (×10−6 g mol−1) R z (nm) R z 2/M w (×103) Dextran content (weight%) D70-g-PАА5 2.15 85 3.36 3.26 D70-g-PАА20 1.43 64 2.87 4.89 PAA 1.40 68 3.23 – The compactness becomes higher as the grafting ratio of the D70-g-PAA samples

increases. However, for D70-g-PAA5 copolymers, this characteristic is close to that of linear PAA macromolecules (Table 1). Star-like D-g-PAA copolymers and linear PAA were transformed into polyelectrolytes. During hydrolysis, some amide groups of the PAA chains were converted into carboxylate ones: Alkaline hydrolysis of D70-g-PAA were not attended by irrelevant processes (breaking or cross-linking of macromolecules) https://www.selleckchem.com/products/qnz-evp4593.html as it was confirmed by SEC analysis of source

and saponified samples. In comparison with linear polyacrylamide, all branched polymers reveal higher values of conversion to anionic form due to compactness of their molecular structure in comparison with linear polymer. It leads to a higher local concentration of functional groups for non-linear polymer molecule (Table 2). Table 2 Conversion degree of polymers (hydrolysis time 30 min) Sample А (%) D70-g-PAA5 35 D70-g-PAA20 37 PAA 28 The viscometry data reveals no polyelectolyte effect but a drastic increase in the 2-hydroxyphytanoyl-CoA lyase intrinsic viscosity for hydrolyzed branched samples with respect to non-ionic ones (Figure 1). It is known that the reduced viscosity of polyelectrolyte solution increases in very dilute regime due to electrostatic repulsions between charged monomers. As it was mentioned above, grafted chains in D70-g-PAA copolymers, even in non-ionic form, have a worm-like or mushroom average conformation that is far from that of a random coil. Hydrolyzed D70-g-PAA copolymer in a salt form acquired limited extended conformation due to appearance of charged functional group. Therefore, its conformation cannot be changed when the concentration is decreased. Figure 1 Concentration dependence of reduced viscosity for hydrolyzed D70- g -PAA5 and D70- g -PAA20 samples.