Relationship Between Oil Uptake and Water Content During Deep-Fat Frying of Potato Particulates Under Isothermal Temperature

The purpose of this study is to correlate water content and oil uptake with the structural changes of potato particulates during deep-fat frying. Raw potato particulates were sliced to form cylinders of 0.006 m diameter × 0.006 m length and subjected to deep-fat frying at isothermal oil temperatures of 160, 190 and 220 °C. The microstructure properties were assessed using a field emission scanning electron microscope (FESEM). Previous results showed that a simultaneous two first-order kinetic model adequately predicted water loss of potato particulates during isothermal frying. In this study, a simple rational model with two parameters in which regression squared (Rsqr) reaches 0.983 shows that oil uptake can be expressed by water content. The cross-sectional structure of potato particulates observed using FESEM is different from the surface structure. Regardless of the frying temperature, pores not only become larger but also increase in number after the transition time. The observations of structural changes at the surface and inner section of potato particulates through the pictures of FESEM are critical. This physical evidence supports our previous assumption that the mechanisms of water loss (two-stage rate processes) before and after transition time are different.     

Acrylate–vinylidene chloride copolymers derived from corresponding water‐borne latexes: Influence of acrylate units on their potential as heavy‐duty anticorrosive coating materials

A series of aqueous latexes with solid contents of 56%–59% were synthesized by binary emulsion copolymerization of vinylidene chloride (VDC) with an acrylate, namely methyl acrylate (MA), ethyl acrylate (EA), butyl acrylate (BA), hexyl acrylate (HA), or 2‐ethylhexyl acrylate (EHA). Differential scanning calorimetry (DSC) and Fourier‐transform infrared (FTIR) spectroscopy showed that the acrylate units with short ester side‐chains, such as MA and EA, made the copolymers hard and the crystallization tendency of their PVDC segments was reduced. Hydrophobic acrylates with relatively long ester groups, such as HA and EHA, gave flexible copolymers, and favored the crystallization of their PVDC segments. BA endowed the copolymers with medium flexibility and crystallization tendency. As coating materials, the copolymers bearing MA and EA adhered poorly to the tinplate before or after 100 hr of salt‐spray corrosion, whereas those bearing BA, HA, or EHA showed good adhesion to tinplate when they had little or no crystallinity. After 100 hr of salt‐spray corrosion, only BA–VDC80, containing 80% VDC, retained both excellent adhesion to metal and excellent barrier performance. Further study demonstrated that BA–VDC80 could protect tinplate from rusting for at least 250 hr under harsh salt‐spray corrosion. Scanning electron microscopy, FTIR‐attenuated total reflectance spectroscopy and DSC were used to evaluate the corroded BA–VDC80 film. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40192.     

Preparation and characterization of porous PDMS beads for oil and organic solvent sorption

In this article, poly (dimethyl siloxane) (PDMS) porous beads were prepared by suspension polymerization method using n‐octane and carbon tetrachloride (CCl₄) as diluents and pore formation agents. The apparent density, porosity and other characteristics were characterized. The absorption experiments showed that the porous PDMS beads exhibited more absorption capacity and faster absorption rate toward oils than the nonporous or oligoporous PDMS beads did, moreover they are of remarkable stability and recyclability, which could provide a path to absorb the oils floating on water. POLYM. ENG. SCI., 54:2965–2969, 2014. © 2014 Society of Plastics Engineers     

Density modeling of polyurethane box foam

A model based on about a dozen fundamental differential equations is used to evaluate and simulate the urethane reactions and physical processes of urethane box foaming. This work focuses on quantitative modeling of foam density for foams using water and physical blowing agents. The final densities of foams range from 30 to 90% of the density as projected with full utilization of the blowing agent. The primary sources of inefficient use of blowing agent are loss of the physical blowing during open‐air mixing and degassing—basically, physical blowing agents with boiling points between 25 and 80°C will evaporate and experience cell rupture in box foams. This loss of blowing agent would not apply to in‐line mixers used for commercial production and should be taken into account with scaling up box or cup foams commercial processes. POLYM. ENG. SCI., 54:1503–1511, 2014. © 2013 Society of Plastics Engineers     

Synthesis and self-assembly of a new amphiphilic thermosensitive poly(N-vinylcaprolactam)/poly(ε-caprolactone) block copolymer

New amphiphilic thermosensitive poly(N-vinylcaprolactam)/poly(ε-caprolactone) (PNVCL-b-PCL) block copolymers were synthesized by ring-opening polymerization of ε-caprolactone with hydroxy-terminated poly(N-vinylcaprolactam) (PNVCL-OH) as a macroinitiator. The structures of the polymers were confirmed by IR, ¹H NMR and GPC. The critical micelle concentrations of copolymer in aqueous solution measured by the fluorescence probe technique reduced with the increasing of the proportion of hydrophobic parts, so did the diameter and distribution of the micelles determined by dynamic light scattering. The shape observed by transmission electron microscopy (TEM) demonstrated that the micelles are spherical. On the other hand, the UV–vis measurement showed that polymers exhibit a reproducible temperature-responsive behavior with a lower critical solution temperature (LCST). The LCST of PNVCL-OH can be adjusted by controlling the molecular weights, and that of copolymers can be adjusted by controlling the compositions and the concentration. Variable temperature TEM measurements demonstrated that LCST transition was the result of transition of individual micelles to larger aggregates.     

Pyrolysis Products of Lignin in Open and Sealed Vessels Studied by Py-GC-MS

The pyrolysis products of lignin in open and sealed vessels were studied by pyrolysis—gas chromatography—mass spectrometry (Py-GC-MS). Several kinds of phenolic derivatives were observed in the pyrolysates in both treatments, while phenolic compounds with alkenyl or acetyl groups had higher relative contents in the open vessel than those in the sealed vessel. Phenol and its alkyl or mono-methoxy substituted derivatives become the main pyrolysis products in the sealed vessel. Most of the lignin pyrolysis products in the open vessel could be detected by Py-GC-MS, but some active products would go through further reaction in the sealed vessel.     

Effects of liquid phases on densification of TiO2-doped Al2O3–ZrO2 composite ceramics

This study investigated the densification behaviors and microstructural evolution of Al₂O₃–ZrO₂ (3Y) composite ceramics doped with four different amounts of TiO₂ (0, 1, 4, and 8 wt%; denoted as 0T, 1T, 4T, and 8T, respectively) to clarify the effect of TiO₂ dopants on densification. The shrinkage rate during densification increased with the increase in the amount of TiO₂. The development of grain boundary feature was also examined. The undoped ceramic showed clean grain boundaries. Thin liquid grain boundary phases were observed in 1T, whereas large liquid phases were found on the grain boundary and at the junction pockets in 4T and 8T. The results were discussed in terms of the relationship between densification and grain boundary feature.     

表面活性剂的性能与应用(Ⅺ)——表面活性剂的泡沫作用及其应用

首先介绍了泡沫的结构和性质,探讨了表面活性剂在泡沫的生成、稳定和破裂中的作用;叙述了表面活性剂的泡沫性能及其评价方法;最后综述了表面活性剂的泡沫性能在浮选分离、油田开发、消防等领域的应用,并对其发展前景进行了展望。     

聚甲醛的耐磨改性研究

选用聚四氟乙烯(PTFE)、石墨、MoS2 3种耐磨改性剂,通过熔融共混法制备聚甲醛(POM)耐磨材料。研究了耐磨改性剂含量对材料力学性能和摩擦磨损性能的影响,并借助扫描电子显微镜(SEM)分析了材料的磨损表面形貌。结果表明,3种耐磨改性剂使POM耐磨材料的力学性能有所下降,但下降幅度并不大。3种耐磨改性剂改性的POM耐磨材料的摩擦磨损性能均得到不同程度的改善,其中PTFE的改善效果最大,当PTFE质量分数为8%时,材料摩擦系数为0.21,较纯POM降低了38%,磨损体积为5×10–4 cm3,较纯POM降低一个数量级。SEM结果表明,PTFE在POM表面形成了均匀分散的转移膜。     

井下用纤维增强连续复合管的性能评价

为保证井下用纤维增强连续复合管使用性能和使用安全,对复合管的耐酸碱腐蚀性能、摩擦磨损性能、承内外压性能等综合性能进行评价。结果表明,该复合管能够承受现场要求的耐内外压、耐拉伸和耐磨损等工况,可以用于井下。