Production and properties of composites based on polymethacrylimides and carbon nanotubes

The eff ect of Taunit grade carbon nanotubes on the kinetic parameters of block radical copolymerization of acrylonitrile and methacrylic acid in the presence of foaming agents (tert-butyl alcohol – N-methylformamide system) was studied. Thermoimidization and foaming of acrylonitrile and methacrylic acid copolymers produced foamed nanocomposites based on polymethacrylimides, carbon nanotubes and finely dispersed silicon oxide. It is shown that the dependences of the density of composites and their strength characteristics on the content of carbon nanotubes pass through a maximum.

Synthetic networks with tunable responsiveness, biodegradation, and molecular recognition for precision medicine applications

Formulations and devices for precision medicine applications must be tunable and multiresponsive to treat heterogeneous patient populations in a calibrated and individual manner. We engineered modular poly(acrylamide-co-methacrylic acid) copolymers, cross-linked into multiresponsive nanogels with either a nondegradable or degradable disulfide cross-linker, that were customized via orthogonal chemistries to target biomarkers of an individual patient’s disease or deliver multiple therapeutic modalities. Upon modification with functional small molecules, peptides, or proteins, these nanomaterials delivered methylene blue with environmental responsiveness, transduced visible light for photothermal therapy, acted as a functional enzyme, or promoted uptake by cells. In addition to quantifying the nanogels’ composition, physicochemical characteristics, and cytotoxicity, we used a QCM-D method for characterizing nanomaterial degradation and a high-throughput assay for cellular uptake. In conclusion, we generated a tunable nanogel composition for precision medicine applications and new quantitative protocols for assessing the bioactivity of similar platforms.

Tablet Disintegrant Derived from Crosslinked Methacrylic Acid and Divinylbenzene Copolymers

Methacrylic acid copolymers crosslinked with 0.25-16 % divinylbenzene were synthesized by free radical polymerization using benzoyl peroxide as an initiator. The products were washed, dried and passed through a 80-mesh sieve prior to determining their infrared spectra, swelling capacity in water and disintegrant efficacy for microcrystalline cellulose (MCC) placebo tablet. The crosslinked methacrylic acid and divinylbenzene copolymers were successfully prepared as indicated by IR spectra, yielding around 50-80 %. The sieved particles of copolymers were white to faint yellow. In contact with water, they hydrated and swelled, where their swelling capacity was lowered with increasing the level of crosslink (divinylbenzene) in the copolymer structure. The copolymer with 0.25 % crosslink caused the MCC tablet to disintegrate fastest (1.2 min), corresponding to its highest swelling capacity. The disintegration efficacy increased with an increase in copolymer concentrations, but decreased with an increase in compression forces.