碳酸丙烯酯脱碳装置技术改造小结

在碳丙脱碳装置中增加了贫液氨冷器 ,改造了碳丙泵 ,增设了变换气氨冷器 ,从而提高了碳丙脱碳装置的吸收和再生效果     

Conducting rubberlike copolymer–carbon fiber composites

Electrically conductive rubberlike copolymer–carbon fiber composites have been prepared by either a solution method or a concentrated emulsion method. In the former procedure, carbon fibers were introduced with stirring in a copolymer–toluene solution, and the polymer–fiber composites were precipitated by extracting the solvent with methanol. In the latter procedure, a pastelike concentrated emulsion of copolymer–toluene solution in an aqueous solution of sodium dodecylsulfate (SDS) was first formed, and the carbon fibers were mechanically blended with the concentrated emulsion. The polymer–carbon fiber composites were precipitated by extracting the toluene and water with methanol. Four kinds of rubberlike copolymers have been used: styrene/ethylene–butylene/styrene triblock copolymer (SES), styrene/butadiene/styrene triblock copolymer (SBS), ethylene/propene/ethylene triblock copolymer (EPE), and ethylene/vinylacetate copolymer (EVA). Short (L = 0.1 mm)- and medium (L = 5 mm)-length carbon fibers were employed. The composites were hot-pressed in a Laboratory Press to form a sheet. The effects of the two methodologies on the electrical conductivity and mechanical properties of the sheets were investigated by changing the type of polymer, the size of the carbon fibers, the volume fraction of the carbon fibers in the composites, and the hot-pressing temperature. Composites with electrical conductivities in the range of 5–14 S/cm, tensile strengths in the range of 10–17 MPa, and elongations at break point larger than 200% were obtained. The conductivities of the composites prepared with the short fibers were by two orders of magnitude smaller than those prepared with medium-size fibers. © 1994 John Wiley & Sons, Inc.     

脂肪酸系列表面活性剂的研究进展

概括和综述了4大类10余个脂肪酸系列表面活性剂的合成、性能和应用现状，重点评述了烷醇酰胺及其衍生物、乙氧基化脂肪酸甲酯、脂肪酸甲酯磺酸盐、N-酰基ED3A、氨基酸、咪唑啉、甜菜碱、双子表面活性剂等脂肪酸系列表面活性剂的研究进展。此系列表面活性剂易生物降解、安全、多功能和高效能。     

用CS－1高效催化剂生产聚丙烯树脂的纺丝试验

研究了用ＣＳ－１高效催化剂生产聚丙烯树脂的纺丝性能，得出采用该催化剂并结合分子量调节剂可以得到熔融指数较大，分子量分布较窄的聚丙烯树脂，其纺丝及力学性能都比较好。     

Radiation flux distribution over solar images formed on the focal plane by a paraboloidal reflector with tracking errors

The radiation flux distribution of off-centered solar images formed by a sun-tracking paraboloidal reflector is theoretically analyzed for several tracking error angles using Jose’s sunshape equation and assuming a specularly reflecting surface without taking meteorological conditions into consideration. The results are printed out by computer in the form of shade density maps to bring out a clear contrast to the low and high flux areas of a full image.     

Grafting polymerization of l-lactide on the surface of hydroxyapatite nano-crystals

A novel method of grafting ring-opening polymerization of l-lactide (LLA) onto the surface of hydroxyapatite nano-particles (n-HAP) was developed. PLLA was directly connected onto the HAP surface through a chemical linkage. The PLLA-g-HAP particles could be stably dispersed in organic solvent such as chloroform for several weeks. The n-HAP particles still retained the original dimension and shape after the grafting of PLLA. Compared with the ³¹P MAS-NMR spectrum of pure HAP powders, there appeared a downfield displacement of 1.2 ppm in the spectrum of PLLA-g-HAP. Fourier transformation infrared (FT-IR) spectra further confirmed the existence of PLLA on the surface of PLLA-g-HAP. The amount of grafted polymer determined by thermal gravimetric analysis (TGA) was about 6% in weight. The tensile strength and elongation at break of the PLLA/PLLA-g-HAP composite containing 8 wt% of PLLA-g-HAP were 55 MPa and about 10-13%, respectively, while those of the PLLA/n-HAP composites were 40 MPa and 3-5%, respectively.     

Optical and surface properties of whey protein isolate coatings on plastic films as influenced by substrate,protein concentration,and plasticizer type

Composite film structures of common plastic polymers including polypropylene (PP) or poly(vinyl chloride) (PVC) with whey protein isolate (WPI) coatings may be obtained by a casting method. Optical and surface properties of the resulting WPI‐coated plastic films, as affected by protein concentration and plasticizer type, were investigated to examine the biopolymer coating effects on surface modification with polymeric substrates of opposite polarity. The measured properties involved specular gloss, color, contact angle, and critical surface energy. Regardless of the substrates, WPI‐coated films possessed excellent gloss and no color, as well as good adhesion between the coating and the substrate when an appropriate plasticizer was added to the coating formulations. The protein concentration did not significantly affect gloss of WPI‐coated plastic films. Among five plasticizers applied, sucrose conferred the most highly reflective and homogeneous surfaces to the coated films. The WPI coatings were very transparent and the coated films with various protein concentrations and plasticizers showed no noticeable changes in color. Experimental results suggest that WPI coatings formulated with a proper plasticizer can improve the visual characteristics of the polymeric substrate and enhance water wettability of the coated plastic films. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 335–343, 2004     

In situ preparation and properties of high‐solid‐content and low‐viscosity poly(methyl methacrylate/n‐butyl acrylate/acrylic acid)/poly(styrene/acrylic acid) composite latexes

With monodispersed poly(methyl methacrylate/n‐butyl acrylate/acrylic acid) [P(MMA/BA/AA)] seeded latex with a particle size of 485 nm and a solid content of 50 wt % as a medium, a series of stable P(MMA/BA/AA)/poly(styrene/acrylic acid) composite latexes with a high solid content (70 wt %) and low viscosities (500–1000 mPa · s when the shear rate was 21 s^?1) was prepared in situ via simple two‐step semicontinuous monomer adding technology. The coagulum ratio of polymerization was about 0.05 wt %. The particle size distribution of such latexes was bimodal, in which the large particle was about 589 nm and the small one was about 80 nm. The latexes combined good mechanical properties with good film‐forming properties. Differential scanning calorimetry showed that the corresponding latex film had a two‐phase structure. The morphology of the latex film was characterized with atomic force microscopy and scanning electron microscopy. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1815–1825, 2007     

Ultrasonic oscillations effect on rheological and processing properties of metallocene‐catalyzed linear low density polyethylene

The effects of ultrasonic oscillations and die materials on die pressure, productivity of extrusion, melt viscosity of metallocene‐catalyzed linear low density polyethylene (mLLDPE), as well as their mechanism were studied in a special ultrasonic oscillations extrusion system developed in our lab. Die materials used in our experiment included steel, brass, and polytetrafluoroethylene (PTFE)_. The experimental results showed that ultrasonic oscillations as well as die materials have great influence on the rheological and processing behavior of mLLDPE. Ultrasonic oscillations can greatly increase the productivity of mLLDPE melt extruded through different dies, and can decrease the die pressure and the melt viscosity of mLLDPE. Compared with steel or brass die, mLLDPE melt extruded through PTFE die is more sensitive to ultrasonic oscillations. A possible mechanism for the improved processability of mLLDPE is proposed in this article. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1873–1878, 2003