Polymers
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2020
·Vol. 12
·期 1
·107
·
IF 3.426
Qinqin Zhang,Xiaoqi Lin,Weisheng Chen,Heng Zhang,Dezhi Han
Many achievements have been made on the research of composite polyurethane foams to improve their structure and mechanical properties, and the composite foams have been widely utilized in building insulation and furniture. In this work, rigid polyurethane foams (RPUFs) with the addition of different fillers (nano-SiO2, peanut shell, pine bark) were prepared through the one-step method. The effects of inorganic nano-SiO2and organic biomass on foam properties were evaluated by means of physical and chemical characterization. The characterization results indicate that the compressive strength values of prepared foams could fully meet the specification requirement for the building insulation materials. The inorganic and organic fillers have no effect on the hydrogen bonding states in composite RPUFs. Furthermore, compared to the biomass fillers, the addition of nano-SiO2greatly influenced the final residual content of the fabricated foam. All composite foams exhibit closed-cell structure with smaller cell size in comparison with the parent foam. The prepared composite foams have the potential for utilization in building insulation.Keywords:rigid polyurethane foam;peanut shell;pine bark;nano-SiO2;insulation materials
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Qianhao Pan,Jiaxing Fang,Shiming Zhang,Yonglin He,Yapei Wang
The spruce bark beetle Ips typographus , as the most notorious pest in Eurasia spruce forest ecosystem, mainly feed on phloem of spruce tree trunk. The concealment of their habit makes regulation of insect population a difficulty to cope with, contributing to spruce forest recession, destruction of environment balance and forest transformation from carbon sinks into carbon source. Based on the cross point between the biorhythm of the I. typographus and photothermal material, description herein was a novel sunlight-triggered biorhythm-paralleled photothermal sponge (BPPS) for continuous control of I. typographus . Three steps including preparation of sugar template based porous polyurethane (PU) sponge, polypyrrole (PPy) modification and pheromone filling were involved in material manufacturing. The attractant and repellant agents were employed into the PU separately to realize a comprehensive regulation on I. typographus behavior. Laboratory simulation and forest field experiments illustrated that both the rapid release within a short period and long-term effectiveness in 21 days were verified. Due to the advantages of designability, cost-effectiveness and environmental friendliness of our sustained-release sponge, this manufacturing strategy offers great promise for generating photothermal responsive sustained-release material, shedding light on long-term control of injurious trunk borers and environmental protection.
研究领域:
昆虫学
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2023
·
IF 5.9
Chuanwei Zhang,Pengfei Zhang,Yanhui Li,S. Nair Sandeep,Jianyong Li,Maocheng Ji,Sixian Peng,Ning Yan,Fangyi Li
Through a single-sided cavity free-form foaming process, composites with open cell structures similar to wood cells were obtained by using corn starch , pulp fiber , and sisal fibers, which was used as the middle layer of the sandwiched composites. Afterwards, more hydrophobic lignin-containing nanocellulose fibrils from pine bark were coated on the surfaces of the open cell composites by high-pressure gun spraying, simulating the bark of wood to impart barrier property to the final product. The water barrier, mechanical property, apparent density, heat insulation, and biodegradability of the sandwich structured bio-composites were characterized. Experimental results indicated that the water contact angle on the surface of the bio-composite was as high as 92°. The apparent density of the bio-composite was very low, at 0.107 g/cm 3 . The tensile strength of the bio-composites reached 5.3 MPa. After conducting biodegradability tests in soil for 60 days, the bio-composites lost 87 % of its mass.
研究领域:
材料科学
·
生物学
✓ 已验证
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2020
·
IF 7.182
Mengting Wang,Jianchu Chen,Shiguo Chen,Xingqian Ye,Donghong Liu
The inhibition effect of three common proanthocyanidins (PA) on the retrogradation properties of maize starch was investigated (including grape seed proanthocyanidins (GSPA), peanut skin proanthocyanidins (PSPA), and pine bark proanthocyanidins (PBPA)). Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis showed that PA could significantly decrease the values of melting enthalpy of retrogradation ( ΔH r ) and the degree of relative crystallinity, suggesting that the starch re-crystallization was retarded by PA. Scanning electron microscope (SEM) characterizations illustrated that retrograded PA-starch samples formed a looser matrix with less appearance of continuous flakes during storage. Overall, 0.5 %–2.0 % of three PAs exhibited suppression of starch retrogradation after 21-day cooling storage, mainly resulting from the PA-starch interaction. Among them, PSPA showed the most substantial inhibition effect on starch retrogradation, which might be attributed to its structural features. This study suggested that PA could be a new type of inhibitor to suppress starch retrogradation.
研究领域:
食品科学
·
化学
·
农业科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）