Lei Chen

Bio: Lei Chen is an academic researcher from Guangdong Ocean University. The author has contributed to research in topics: Adsorption & Thermal stability. The author has an hindex of 1, co-authored 1 publications receiving 5 citations.

Fabrication of hydrophobic NiFe2O4@poly(DVB–LMA) sponge via a Pickering emulsion template method for oil/water separation

Abstract: Super-hydrophobic porous absorbents are convenient, low-cost, efficient and environment-friendly materials in the treatment of oil spills. In this work, a simple Pickering emulsion template method was employed to fabricate an interconnected porous poly(DVB-LMA) sponge. A new co-Pickering stabilization system of Span 80 and NiFe2O4 nanoparticles was used to prepare ultra-concentrated internal phase water-in-oil (W/O) emulsions. After further polymerization, the resulting sponges were generated, which exhibited excellent adsorption selectivity due to the super-hydrophobicity and super-lipophilicity. Furthermore, the characterization results indicated that the composites had superior thermal stability, low density, high porosity and a flexible three-dimensional porous structure. Besides, the addition of nickel ferrite nanoparticles provided the materials with extra magnetic operability. High oil adsorption capacity (up to 36.9-84.2 g g-1), high oil retention, fast adsorption rate and superior reusability allowed the materials to be applied in the treatment of oily water.

Degradable and processable polymer monoliths with open-pore porosity for selective CO2 and iodine adsorption.

Abstract: A task-specific design of biodegradable and processable porous polymers is one of the primary requisite for their efficient day-to-day use to minimize polymer waste Herein, a surfactant (or additive)-free method is reported for the synthesis of a processable and degradable aliphatic open-pore porous polyelectrolyte monolith for the removal of gaseous pollutants such as iodine and CO2 This is achieved via a colloidal templating method In the 1st stage, cationic colloidal nanoparticles containing reactive amines and acrylamide groups were formed via the phase separation of hyperbranched polyaminoamides in water (sol) These cationic nanoparticles (which acted as both templates and macromers) further reacted to form a gel, which upon freeze-drying leads to the formation of a polymer monolith with an open-pore porous morphology and hierarchical porosity throughout its structure During gelation, the shape of the monolith can be controlled using suitable templates and a similar strategy was used to prepare porous thin films The monolith has shown excellent iodine adsorption ability (5000 mg g−1 in the vapor phase and 2663 mg g−1 in the solution phase) with good reusability and CO2 adsorption ability (60 mg g−1), with CO2/CH4 and CO2/N2 selectivities of 185 and 67, respectively The degradability of the materials was studied in detail at different pH, confirming their easy degradability in aqueous solutions and a higher degradability at basic pH

Emulsion-templated porous polymers: drying condition-dependent properties.

Abstract: Macroporous materials templated using high internal phase emulsions (HIPEs) are promising for various applications. To date, new strategies to create emulsion-templated porous materials and to tune their properties (especially wetting properties) are still highly required. Here, we report the fabrication of macroporous polymers from oil-in-water HIPEs, bereft of conventional monomers and crosslinking monomers, by simultaneous ring-opening polymerization and interface-catalyzed condensation, without heating or removal of oxygen. The resulting macroporous polymers showed drying condition-dependent wetting properties (e.g., hydrophilicity–oleophilicity from freezing drying, hydrophilicity–oleophobicity from vacuum drying, and amphiphobicity from heat drying), densities (from 0.019 to 0.350 g cc−1), and compressive properties. Hydrophilic–oleophilic and amphiphobic porous polymers turned hydrophilic–oleophobic simply by heating and protonation, respectively. The hydrophilic–oleophobic porous polymers could remove a small amount of water from oil–water mixtures (including surfactant-stabilized water-in-oil emulsions) by selective absorption and could remove water-soluble dyes from oil–water mixtures. Moreover, the transition in wetting properties enabled the removal of water and dyes in a controlled manner. The feature that combines simply preparation, tunable wetting properties and densities, robust compression, high absorption capacity (rate) and controllable absorption makes the porous polymers to be excellent candidates for the removal of water and water-soluble dyes from oil–water mixtures.

Peptide hydrogel based sponge patch for wound infection treatment

Abstract: Dressing with the function of anti-wound infection and promoting skin repair plays an important role in medicine, beauty industry, etc. In terms of anti-wound infection, traditional dressings, such as gauze, have problems such as excessive bleeding in the process of contact or removal, and slow wound healing due to poor biological compatibility. The development of new functional and biocompatible dressings has essential application value in biomedical fields. In this study, a new type of dressing based on polypeptide functional sponge patch was constructed. The porous sponge patch is made of antimicrobial peptide and medical agarose through gel and freeze-drying technology. In vitro antibacterial experiments and small animal skin wound infection model experiments show that the porous sponge has excellent antibacterial and anti-skin infection activities, as well as the function of promoting wound healing.