title: Synthesis, characterization, and morphology study of poly(acrylamide-co-acrylic acid)-grafted-poly(styrene-co-methyl methacrylate) "raspberry"-shape like structure microgels by pre-emulsified semi-batch emulsion polymerization.
abstract: A novel microgels were polymerized using styrene (St), methyl methacrylate (MMA), acrylamide (AAm), and acrylic acid (AAc) monomers in the presence of N,N'-methylenebisacrylamide (MBA) cross-linker. Pre-emulsified monomer was first prepared followed by polymerizing monomers using semi-batch emulsion polymerization. Fourier Transform Infrared Spectroscopy (FTIR) and (1)H Nuclear Magnetic Resonance (NMR) were used to determine the chemical structure and to indentify the related functional group. Grafting and cross-linking of poly(acrylamide-co-acrilic acid)-grafted-poly(styrene-co-methyl methacrylate) [poly(AAm-co-AAc)-g-poly(St-co-MMA)] microgels are approved by the disappearance of band at 1300 cm(-1), 1200 cm(-1) and 1163 cm(-1) of FTIR spectrum and the appearance of CH peaks at 5.5-5.7 ppm in (1)H NMR spectrum. Scanning Electron Microscope (SEM) images indicated that poly(St-co-MMA) particle was lobed morphology coated by cross-linked poly(AAm-co-AAc) shell. Furthermore, SEM results revealed that poly(AAm-co-AAc)-g-poly(St-co-MMA) is composite particle that consist of "raspberry"-shape like structure core. Internal structures of the microgels showed homogeneous network of pores, an extensive interconnection among pores, thicker pore walls, and open network structures. Water absorbency test indicated that the sample with particle size 0.43 μm had lower equilibrium water content, % than the sample with particle size 7.39 μm.
authors.affiliation: Department of Polymer Engineering, Faculty of Chemical Engineering, Universiti Teknologi Malaysia (UTM), 81310 Skudai, Johor, Malaysia. razlinawati2@live.utm.my
authors.forename: Ros Azlinawati
authors.initials: RA
authors.lastname: Ramli
authors.forename: Shahrir
authors.initials: S
authors.lastname: Hashim
authors.forename: Waham Ashaier
authors.initials: WA
authors.lastname: Laftah
mesh_terms: D000042:Absorption; D000178:Acrylamides / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry*; D005782:Gels / Q000138:chemical synthesis*; D008855:Microscopy, Electron, Scanning; D019906:Nuclear Magnetic Resonance, Biomolecular; D010316:Particle Size; D058105:Polymerization; D011109:Polymethacrylic Acids / Q000138:chemical synthesis*; D011137:Polystyrenes / Q000138:chemical synthesis*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D000178:Acrylamides; D004655:Emulsions; D005782:Gels; D011109:Polymethacrylic Acids; D011137:Polystyrenes; C431184:poly(acrylamide-co-acrylic acid)