Search results
Results From The WOW.Com Content Network
Other polymers formed by cationic polymerization are homopolymers and copolymers of polyterpenes, such as pinenes (plant-derived products), that are used as tackifiers. In the field of heterocycles, 1,3,5-trioxane is copolymerized with small amounts of ethylene oxide to form the highly crystalline polyoxymethylene plastic.
Living cationic polymerization is a living polymerization technique involving cationic propagating species. [1] [2] It enables the synthesis of very well defined polymers (low molar mass distribution) and of polymers with unusual architecture such as star polymers and block copolymers and living cationic polymerization is therefore as such of commercial and academic interest.
Thiolated polymers are capable of providing a comparatively more pronounced increase in viscosity after application, as an extensive crosslinking process by the formation of disulfide bonds between the polymer chains due to oxidation takes place. This effect was first described in 1999 by Bernkop-Schnürch et al. [29] for polymeric excipients.
Polymers of different architectures will self-assemble into different structures. This self-assembly can occur due to the nature of the polymer and the solvent, or due to a change in pH. pH changes can also cause the larger structure to swell or deswell. For example, block copolymers often form micelles, as will star polymers and branched polymers.
Polystyrene sulfonates can bind to various drugs within the digestive tract and thus lower their absorption and effectiveness. Common examples include lithium, thyroxine, and digitalis. In September 2017, the FDA recommended separating the dosing of polystyrene sulfonate from any other oral medications by at least three hours to avoid any ...
Living polymerization: A chain polymerization from which chain transfer and chain termination are absent.. Note: In many cases, the rate of chain initiation is fast compared with the rate of chain propagation, so that the number of kinetic-chain carriers is essentially constant throughout the polymerization.
Another type of lipid-nanoparticle that can be used for drug delivery to the brain is a cationic liposome. These are lipid molecules that are positively charged. [6] One example of cationic liposomes uses bolaamphiphiles, which contain hydrophilic groups surrounding a hydrophobic chain to strengthen the boundary of the nano-vesicle containing ...
The journal is abstracted and indexed in Scopus and the Science Citation Index Expanded.According to the Journal Citation Reports, its 2020 impact factor is 1.756, ranking it 141st out of 160 journals in the category "Biotechnology & Applied Microbiology", [1] 37th out of 41 journals in the category "Materials Science, Biomaterials", [2] and 69th out of 91 journals in the category "Polymer ...