Micelles of PAAm-b-PEO-b-PAAm Triblock Copolymers and Their Binding with Prednisolon

Abstract

The IntraPC forming asymmetric PAAm-b-PEO-b-PAAm triblock copolymers (TBCs) composed of poly(ethylene oxide) (M _v  = 6 · 10³ and 1.4 · 10⁴) and polyacrylamide of a variable chain length form “hairy-type” micelles in water and “flower-like” micelles at the addition of EtOH > 40 vol %. The specific micellization is developed in TBC aqueous/ethanol solutions (EtOH content < 30 vol %) at the PS introduction. It is caused by the binding of PS with TBC micelles due to hydrogen bonds and hydrophobic interactions. The amorphous structure of TBCs and polymorphic crystalline structures of PS are found. The products of the interaction of TBC and PS contain highly ordered crystalline structures of the drug. But it is possible to avoid the drug crystallization at low PS contents.

Keywords:

• Drug
• intramolecular polycomplex
• micellization
• nanocontainer
• triblock copolymer

Notes

¹The critical micellization concentration.

²The Gibbs free micellization energy.

¹The glass transition temperature.

²The temperature range for corresponding thermal transition.

³The specific capacity jump.

⁴The melting tenperature.

⁵The melting enthalpy.

⁶The crystallinity degree: , where is the melting enthalpy for 100% crystalline polymer (196.8 J · g⁻¹).

⁷The compositions of the initial TBC + PS blends ϕ = 0.64 mol_PS/base-mol_TBC.

¹The scattering angle corresponding to the diffraction peak maximum.

²The average interplane distance.