Two-dimensional lamellar phosphogypsum/polyethylene glycol composite PCM: Fabrication and characterization

Jinfen Lou,Kai Zhang,Shuhao Qin,Yang Lei,Yufei Liu,Min He,Jie Yu 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.113 No.-

In this work, a nanocomposite phase change material (PCM) has been designed by combining twodimensionallamellar anhydrous calcium sulfate with polyethylene glycol (PEG). We report a facile strategyto controllably fabricate two-dimensional lamellar anhydrous calcium sulfate (LAH) with the averagethickness of 28.63 nm from phosphogypsum (PG) through ethylenediamine tetraacetic acid disodium(Na2EDTA) induction in glycerol and ethylene glycol solutions at 98 C. The obtained 2D lamellarCaSO4 was a slit-type mesoporous material stacked by the nanosheet of calcium sulfate. It has a specificsurface area of 70.02 m2/g, which is 10 times larger than phosphogypsum. Na2EDTA acts as a crystalhabit-directing agent to regulate crystal morphology through nonclassical nanoparticle-mediated crystallizationprocesses, resulting in the crystalline morphology tending to be lamellar. Lamellar anhydrouscalcium sulfate phase change composites (LAHPCMs) were prepared with 2D lamellar anhydrous nano-CaSO4 and polyethylene glycol (PEG). The LAHPCMs had a high latent heat storage capacity (92.99 J/g). Lamellar anhydrous calcium sulfate phase change composites have good thermal stability and durability,structure stability, and good liquid leakage resistance. These results provide the possibility for phosphogypsumto be used for energy storage and thermal insulation.

Influence of Reaction Conditions on the Grafting Pattern of 3-Glycidoxypropyl trimethoxysilane on Montmorillonite

He, Wentao,Yao, Yong,He, Min,Kai, Zhang,Long, Lijuan,Zhang, Minmin,Qin, Shuhao,Yu, Jie Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.1

Surface modification of montmorillonite (MMT) with 3-glycidoxypropyl trimethoxysilane (3GTO) in mild methanol/water mixture has been investigated in detail. The influence of reaction conditions (including silane concentration in feed, reaction time and reaction temperature) on the grafting amount and yield of silane, and further on the grafting pattern of silanes was studied by thermogravimetric analysis, elemental analysis, X-ray diffraction (XRD) and BET. Higher silane concentration, longer reaction time and higher reaction temperature are all benefit to higher grafting amount. When the grafting reaction was performed with 3 mmol/g silane concentration, at $90^{\circ}C$ for 24 h, the grafted amount and yield of silane reached 1.4443 mmol/g and 30%, respectively. Based on the XRD and BET data analysis, a speculation that the grafting pattern of silanes was concentration dependence was proposed.

Surface Modification of Colloidal Silica Nanoparticles: Controlling the size and Grafting Process

Wentao He,Danhua Wu,Juan Li,Kai Zhang,Yushu Xiang,Lijuan Long,Shuhao Qin,Jie Yu,Qin Zhang 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.9

Surface modification of colloidal silica nanoparticles without disrupting the electric double layer of nanoparticles is a major challenge. In the work, silane was employed to modify colloidal silica nanoparticles without inducing bridge flocculation obviously. The effect of pH value of the silica sol, the amount of silane in feed, and reaction temperature on the graft amount and the final size of modified particles was investigated. The increased weight loss by TG and the appearance of T2 and T3 except for Q2 and Q3 signals by CP/MAS 29Si NMR of the modified samples verified the successful grafting of silane. The graft amount reached 0.57 mmol/ g, which was slightly lower than theory value, and the particle size remained nearly the same as unmodified particles for acidic silica sol at the optimum condition. For alkaline silica sol after modification, aggregates composed of several nanoparticles connected together with silane moleculars as the bridge appeared.

Influence of Reaction Conditions on the Grafting Pattern of 3-Glycidoxypropyl trimethoxysilane on Montmorillonite

Wentao He,Yong Yao,Min He,Zhang Kai,Lijuan Long,Minmin Zhang,Shuhao Qin,Jie Yu 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.1

Surface modification of montmorillonite (MMT) with 3-glycidoxypropyl trimethoxysilane (3GTO) in mild methanol/water mixture has been investigated in detail. The influence of reaction conditions (including silane concentration in feed, reaction time and reaction temperature) on the grafting amount and yield of silane, and further on the grafting pattern of silanes was studied by thermogravimetric analysis, elemental analysis, X-ray diffraction (XRD) and BET. Higher silane concentration, longer reaction time and higher reaction temperature are all benefit to higher grafting amount. When the grafting reaction was performed with 3 mmol/g silane concentration, at 90 oC for 24 h, the grafted amount and yield of silane reached 1.4443 mmol/g and 30%, respectively. Based on the XRD and BET data analysis, a speculation that the grafting pattern of silanes was concentration dependence was proposed.

Constructing Microstructures of Chlorinated Polyvinyl Chloride Microporous Membranes by Non-solvent Induced Phase Separation for High Permeate Flux and Rejection Performance

Xiaomei Zhan,Jifeng Cheng,Li Xiang,Huiju Shao,Shuhao Qin 한국섬유공학회 2021 Fibers and polymers Vol.22 No.5

To obtain the excellent permeate flux, rejection performance and mechanical properties, the chlorinated polyvinylchloride (CPVC) porous membrane was fabricated on the polyethylene terephthalate (PET) non-woven fabric by non-solventinduced phase separation (NIPS), using Tween80 (polyoxyethylene sorbitan monooleate) as a hydrophilic surfactant to regulate themicrostructure of the membrane. Porous skin layer and sub-layer were achieved when 3 wt.% Tween80 was added with asmall amount of deionized water as additive, and internal layer consisted of various finger-like holes. The forming mechanism ofmicrostructures was investigated according to the effects of Tween80 molecular chain structure on the viscosity and surface tensionof casting solution. Significantly, the modified membranes obviously exhibited higher pure water flux, which was increasedby 257 % compared with the pristine membrane. The rejection to ink suspension was over 99 %. Furthermore, the antifoulingperformance of modified membrane was also greatly improved on account of the above microstructure and more hydrophilicsurface. This study provides a new idea for the construction of membrane microstructure and the hydrophilic modification.

Surface Modification of Colloidal Silica Nanoparticles: Controlling the size and Grafting Process

He, Wentao,Wu, Danhua,Li, Juan,Zhang, Kai,Xiang, Yushu,Long, Lijuan,Qin, Shuhao,Yu, Jie,Zhang, Qin Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.9

Surface modification of colloidal silica nanoparticles without disrupting the electric double layer of nanoparticles is a major challenge. In the work, silane was employed to modify colloidal silica nanoparticles without inducing bridge flocculation obviously. The effect of pH value of the silica sol, the amount of silane in feed, and reaction temperature on the graft amount and the final size of modified particles was investigated. The increased weight loss by TG and the appearance of $T_2$ and $T_3$ except for $Q_2$ and $Q_3$ signals by CP/MAS $^{29}Si$ NMR of the modified samples verified the successful grafting of silane. The graft amount reached 0.57 mmol/g, which was slightly lower than theory value, and the particle size remained nearly the same as unmodified particles for acidic silica sol at the optimum condition. For alkaline silica sol after modification, aggregates composed of several nanoparticles connected together with silane moleculars as the bridge appeared.

Tung Oil Anhydride Modified Hemp Fiber/Polypropylene Composites: The Improved Toughness, Thermal Stability and Rheological Property

Hongming Wu,Dinghong Xu,Ying Zhou,Chengtao Gao,Jianbing Guo,Weidi He,Yong He,Shuhao Qin 한국섬유공학회 2020 Fibers and polymers Vol.21 No.9

Natural fibers reinforced composites (NFCs) have renewable and low cost advantages. In this paper, the tung oilanhydride (TOA) modified polypropylene (PP)/hemp fiber composites have been prepared by a melt-blended process. Thereaction between the tung oil anhydride and the as-treated hemp fiber make the TOA molecules to accumulate on the surfaceof hemp fiber and to form a TOA layer on the surface of hemp fibers, which is confirmed by the FT-IR and SEM analyses. The TOA layer improves the compatibility between PP matrix and hemp fibers. The elongation at break (EB) and impactstrength of the PP/hemp fiber/TOA composites are twice more than the PP/hemp fiber composites. Thermal analysis showsthe Toneset and Tmax of the composites increasing that reflects the thermal stability of the composites improved. The crystallineproperty reveals that the Tc moves to high temperature with the TOA or hemp fiber added in the blends. The DMA andrheology properties analysis indicate that the TOA layer improved molecular mobility of the composites and show a shearthinning effect.