Table 8.

Polymers used in the development of controlled release drug delivery systems.

Synthetic Polymers [66,67]	Natural Polymers [67,68]	Stimuli-Responsive Polymers [69]
Polyhydroxy ethyl methacrylate poly (2-hydroxyethyl methacrylate) Ethyl cellulose Hydroxypropyl methyl cellulose (HPMC) Eudragits Polylactic acid (PLA) Polylactic-co-glycolic acid (PLGA) Polycaprolactone Polyvinyl Pyrrolidone (PVP) Poly methyl methacrylate (PMMA) Poly-(N-Isopropyl acrylamide) (PNIPAM) Poly(ethylenimine) Cyclodextrin (α, β, γ) Carbomers	Alginates Starches Dextrans Cellulose Gums (Acacia, Tragacanth, Guar gum) Chitosan Collagen Gelatine Microbial polymers (Polyhydroxy butyrate) Arginine derivatives	pH-responsive: Polyacids (PLA, Polymethacrylate, Poly aspartate, alginates, polystyrene sulphonic acid) Polybases (Chitosan, poly-L-Lysine, Polyallylamine, Poly ethylene amine, Poly amidoamine dendrimer) Thermoresponsive: Poly-(N-Isopropyl acrylamide) (PNIPAM) Poly-(N-Vinylcaprolactam) Poly(N,N-dimethyl acrylamide) Poly (methyl vinyl ether) Electric responsive: Sulfonated polystyrenes Poly(thiophene)s Poly(ethyl oxazoline)s Ultrasound responsive: Ethylene-vinyl acetate Light responsive: Modified poly(acrylamide)s