KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Settings

Author: search.filters.author.Suteewong, TeerapornSubject: search.filters.subject.Coating

Search Results

Now showing 1 - 3 of 3
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Fabrication of hollow magnetic polyaniline particles via in-situ polymerization in one-pot for UV–Vis-NIR and EMI applications
    (2024-01-01)
    Promlok, Duangkamol
    ;
    Wichaita, Waraporn
    ;
    Phongtamrug, Suttinun
    ;
    Kaewsaneha, Chariya
    ;
    Sreearunothai, Paiboon
    The concern on the adverse impacts of electromagnetic (EM) pollution has continuously increased. Instead of using heavy metal sheet, this work aims to develop magnetic polymeric particles, that can easily be incorporated in coatings, for EM/ultraviolet-visible-near infrared (UV–Vis-NIR) shielding. By carefully design structure and key components, hollow magnetic (HoM) polyaniline (PANI) particles possessing a void encircled with magnetic nanoparticles dispersed in PANI semi-conductive shell were fabricated via the oxidative polymerization in emulsion system. By using ethyl benzene as a soft template and different surfactive dopants, i.e., sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, and poly(sodium 4-styrenesulfonate) (PSS), the HoM-PANI particles (0.5–2 μm) with well-defined hollow structure, high magnetic loading (17–21%wt), and superparamagnetic properties were obtained. The particle size distribution, and magnetic loading were slightly affected by the reaction temperature, whereas molecular weight (M<inf>w</inf>) of the localized dopant considerably influenced on the levels of interparticle connectivity, and hence, the conductivity could be tailored. The water dispersible HoM-PANI particles could form opaque coating, and free-standing film. PSS with M<inf>w</inf> of 70 K and 1 M yielded the larger HoM-PANI particles and more opaque films than small dopant molecules. Void size was the determining effect on excellent opacity of the coating containing HoM-PANI dispersed in poly(vinyl alcohol) matrix against UV–Vis-NIR, and EM radiation. The ability to tune their optical properties, and electrical conductivity accomplished by designing the particle nanostructure, and doping/de-doping by localized dopants enables them the promising candidates for functional paint, and film for irradiation protection.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Hollow natural rubber latex particles as bio-based alternative white pigment for coating applications
    (2022-11-15)
    Promlok, Duangkamol
    ;
    Sonongbua, Kritayakorn
    ;
    Wilepsuwan, Mutita
    ;
    Suteewong, Teeraporn
    ;
    Tangboriboonrat, Pramuan
    Due to the broad particle size distribution as well as non-spherical shape of natural rubber (NR) latex particles, the non-collapse hollow NR latex particles (HL-NRPs) with well-defined void structure were developed aiming to use as an eco-friendly white pigment/additive for coatings. These hybrid HL-NRPs were prepared via the seeded emulsion polymerization of methyl methacrylate/divinylbenzene/acrylic acid (MMA/DVB/AA) monomers on NR core particles in one-pot. Using cumene hydroperoxide (CHP)/tetraethylene pentamine (TEPA) as a redox initiator, the copolymerization occurred at the particle/water interface. Without seed removal, a single void inside NRP was in situ formed by the phase separation process. Hydrophobic and elastic NR became the inner wall which strengthened the HL particles. Whereas its indigenous stabilizers, i.e., proteins-lipids, allowed the osmosis from the aqueous medium to further expand the void. The proposed mechanism was illustrated using oleic acid (OA) as a model fatty acid for non-rubber substances. Since the multiple light scattering inside the hollow structure could enhance their refractive index, the optical performance of HL-NRPs as a low-density opacifying agent in poly(vinyl alcohol) matrix, was examined using UV-Vis spectroscopy. Results showed that the HL-NRPs-based films exhibited high blocking ability over UV and visible regions. Moreover, the HL-NRPs coated with chitosan (CS) enabled these nanocomposites to adsorb the formaldehyde vapor. For sustainable development, HL-NRPs/CS could potentially be a green alternative white pigment/additive for coatings.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Facile control of structured ZnO polymeric nanoparticles through miniemulsion polymerization: Kinetic and UV shielding effects
    (2021-08-01)
    Sudjaipraparat, Narissara
    ;
    Suteewong, Teeraporn
    ;
    Tangboriboonrat, Pramuan
    Zinc oxide polymeric nanoparticles (ZPPs) of poly (styrene-co-acrylic acid) P(St/AA), containing oleic acid modified zinc oxide nanoparticles (OA-ZnO NPs), were synthesized via miniemul-sion polymerization. By simply adjusting the quantity of reactants, i.e., sodium dodecyl sulfate (SDS) surfactant, potassium persulfate (KPS) initiator, and divinyl benzene (DVB) crosslinking agent, the location of ZnO NPs were altered from the inner (core) to the outer (shell), leading to core-shell and Pickering-like morphologies, respectively. The Pickering-like ZPPs were obtained when using SDS at below or equal to the critical micelle concentration (CMC). At above the CMC, the complete en-capsulation of OA-ZnO NPs within the ZPPs depicted a kinetically controlled morphology. The transition to Pickering-like ZPPs also occurred when reducing the KPS from 2 to 0.5–1%. Whereas the DVB accelerated the polymerization rate and viscosity in the growing monomer-swollen nanodroplets and, hence, contributed to kinetic parameters on particle morphology, i.e., an increase in the DVB content increased the rate of polymerization. A hollow structure was obtained by replacing styrene with the more hydrophilic monomer, i.e., methyl methacrylate. All ZPPs-incorporated poly (vinyl alcohol) (PVA) films greatly improved shielding performance over the UV region and were relatively transparent on a white paper background. Due to the large number of ZnO NPs in the central region and, hence, the ease of electron transfer, composite films containing core-shell ZPPs possessed the highest UV blocking ability. ZnO NPs in the outer part of the hollow and Pickering-like ZPPs, on the other hand, facilitated the multiple light scattering according to the difference of refractive in-dices between the inorganic shell and organic/air core. These results confirm the advantage of structured ZPPs and their potential use as transparent UV shielding fillers.