SURFACE & COATINGS TECHNOLOGY
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2018
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IF 2.906
Qiwen Yong,Bing Liao,Jianheng Huang,Ying Guo,Caizhen Liang,Hao Pang
A novel waterborne polyurethane (WPU) resin with low gloss and micro-roughness was synthesized by the prepolymer and self-emulsification method. It was achieved by introducing multi-hydroxyl castor oil and reactive bisphenol A-type epoxy E-44 or E-51 resin to polyurethane prepolymer to form a cross-linking network structural waterborne polyurethane emulsion, which demonstrated the distinctive characteristic of the shear-thinning pseudoplastic fluid with a yield stress. The chemical structures and rough surface morphologies of the WPU films were characterized by FTIR-ATR, LCRS , AFM , SPMS and SEM, respectively. The specular gloss values at 20°, 60° and 85° incident angles were measured, and the values of different kinds of roughness parameters were obtained. The relationship between the gloss and the castor oil content was also discussed in detail. In general, this WPU resin endowed the film with micro-roughness, moderate hardness and good adhesive strength , making it very prospective in substitution for the traditional low gloss coatings.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
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2021
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IF 5.161
Taoling Xie,Weiyao Kao,Zetian Zhang,Yang Liu,Zhengjun Li
A new type of low gloss waterborne self-matting acrylate polymer with core-shell structure was successfully synthesized. The organosilane ϒ-methacryloxy propyl trimethoxyl silane (ϒ-MPS) was used as a crosslinking agent, which can control and modulate the surface micro-roughness of acrylate polymer films. The self-matting acrylate polymer has good latex stability containing no external powdery matting agent. In particular, the gloss value can reach as low as 6.3 units at an incident of 60° when the amount of ϒ-MPS is 7% based on the total mass of the shell monomer. Moreover, the main factors affecting glossiness, such as crosslinking degree, surface roughness, migration of organosilicon moieties to the surface and phase separation, were studied in detail. The observation by scanning electron microscope and atomic force microscope indicated that the surface roughness was elevated with the increase of the ϒ-MPS content. Besides, the transmission electron microscope observation and differential scanning calorimeter analysis revealed that the acrylate polymers displayed microphase separation behavior, which combined with the surface roughness could increase the scattered and diffused lights, thereby endowing the coating with the matte effect. In addition, due to the incorporation of ϒ-MPS, the crosslinking density and hydrophobicity increased, and thereby thermal stability, tensile strength and water resistance of the films were also improved. Therefore, this work provides practical prospects for the industrial application of organosilicon modified acrylate polymer in the field of matte coatings.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
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2021
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IF 5.161
Zhengmao Ding,Jie Li,Wei Xin,Jun Zhu,Yunjun Luo
With the change of people's aesthetic concepts, low-gloss coatings are becoming a new hotspot of interest. However, the low-gloss waterborne polyurethane (WPU) coatings reported by others to our knowledge are all single-functional coatings, which are difficult to meet the requirements of complex application environments. Herein, a series of low-gloss WPU nanocoatings with versatility via mono-layered organic montmorillonite (OMt) nanosheets is reported, and then applied to polyester fabric. Ultraviolet-visible (UV–vis) examination indicated that the OMt nanosheets made the as-prepared nanocoatings have unique UV-shielding performance. Thermogravimetric analysis (TGA) curves showed that the OMt nanosheets increased the thermal stability of the nanocoatings. Moreover, Fourier transforms infrared (FTIR) spectroscopy confirmed the existence of hydrogen bonds between OMt nanosheets and WPU molecular chains, which is the essential reason why the nanocoating had a matte level of 60° gloss of 1.9 GU on the fabric. Rougher surface topography of the nanocoating compared with pristine WPU coating and fabric observed by scanning electron microscopy (SEM) is the direct reason for the decrease in gloss. In addition, the influence of the times of scraping on the gloss of the coatings was also studied. Thus, our research may provide new insights for the multifunctional matte WPU coatings.
研究领域:
材料科学
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表面化学
✓ 已验证
产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
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2019
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IF 3.42
Zhengmao Ding,Jie Li,Wei Xin,Guangpu Zhang,Yunjun Luo
A series of low gloss organic montmorillonite/waterborne polyurethane nanocomposite (OWPU) coatings with polycaprolactone (PCL) and hydroxyl terminated polybutadiene (HTPB) were prepared, characterized and then applied to polyvinyl chloride leather. Small-angle XRD and TEM examinations indicated that montmorillonite was exfoliated into individual single-layer nanosheets in HTPB, and retained separate shapes in subsequent synthesis and preparation. The OWPU dispersions with higher nanosheets contents exhibited a larger average particle size and a less negative zeta potential obtained through DLS. A rougher coating surface topography of OWPU compared with pristine WPU was observed by SEM, which reduced the 60° gloss to 4.6 GU within the matt range. Moreover, TGA results indicated that the nanosheets effectively increased thermal stability of hard segments and soft segments derived from PCL, but had little effect on that of soft segments derived from HTPB. Furthermore, rheological analysis confirmed the nanosheets promoted cross-linking and cyclization of HTPB at high temperature, thereby imparting anti-dripping properties to OWPU coatings. Cone calorimeter test and SEM results showed that flame retardancy of OWPU was improved by forming a charred layer with sheet-cluster structure. In addition, incorporation of the nanosheets was also capable of changing the surface touch feeling of OWPU coatings from sticky to some dry alike.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）