Publications by authors named "Choong Ping Sen"

Objective: This research investigates how particle parameters, such as zeta potential, size, functional group, material composition, and hydrophobicity affect their affinity and deposition of particles onto hair.

Methods: Streaming potential was used as the technique for analysis. The streaming potential data obtained was then converted to surface coverage data.

View Article and Find Full Text PDF
Article Synopsis
  • Polyurethane foams are typically made from toxic chemicals, but nonisocyanate polyurethane (NIPU) offers a safer alternative that hasn't been thoroughly researched due to challenges in creating foams.
  • The study focused on synthesizing amine-CO adducts and their ability to absorb and release carbon monoxide (CO), achieving significant CO desorption rates.
  • Successfully, these amine-CO adducts were utilized as a foaming agent to create low-density NIPU foams through heating, demonstrating a new approach to foaming without harmful isocyanates.
View Article and Find Full Text PDF

Polymer coatings having high amounts of renewable carbon and self-healing properties are highly sought after in a sustainability perspective. We report here the development of bio-/CO-derived nonisocyanate polyurethane (NIPU) coatings which are recyclable and healable via three different types of healing mechanisms. These NIPUs contain furan rings in their main chain which after cross-linking with bismaleimides form organogels having a thermo-reversible sol-gel transition and solvent-borne coatings with improved properties.

View Article and Find Full Text PDF

A solution-based chemical synthesis of two graphene nanoribbons with armchair edges is reported. The precursor oligophenylene molecules are synthesized and subjected to oxidative cyclodehydrogenation to afford the target molecules, G-1 and G-2. These molecules have good solubility in organic solvents, and show a large redshift in their absorption edge (up to 185 nm) and emission maximum (up to 125 nm) after planarization.

View Article and Find Full Text PDF

Conjugated polymers with strong photophysical properties are used in many applications. A homopolymer (P1) and five new low band gap copolymers based on 4,4'-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) and acceptors 3,6-dithienyldiketopyrrolopyrrole (P2), phthalimide (P3), benzotriazole (P4), 4,7-dithienyl[1,2,3]triazolo[4,5g]quinoxaline (P5), and 2,5-dithienylthieno[3,4-b]pyrazine (P6) were prepared by means of Sonogashira polymerization. The characterization of polymers by using (1) H NMR, absorption, and emission spectroscopy is discussed.

View Article and Find Full Text PDF