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101.
T. Crutcher K. R. Smith J. E. Borland J. D. Sauer J. W. Perine 《Journal of the American Oil Chemists' Society》1992,69(7):682-689
The interaction of solid alkyldimethylamine oxide and ditallowdimethylammonium chloride (DTMAC) and ditallow dimethylammonium
sulfate (DTMAS) quats in representative types of fabric softener systems was studied with particular focus on synergistic
behavior. Softening, whiteness retention, wetting, static build-up and detersiveness were evaluated for laundry rinses, laundry
detergents and dryer sheets. In laundry rinses, blends of amine oxide and DTMAC proved to be synergistic for improving the
wetting of cotton towels. Although no synergism was observed in laundry detergents, formulations containing amine oxide gave
better detersiveness than systems with DTMAC without the splotching associated with the quaternary salt. In dryer sheets,
it was discovered that blends of amine oxide and DTMAS gave synergistic softening of cotton towels and were unexpectedly effective
in preventing static charge build-up on polyester fabric. 相似文献
102.
C. Joe Toney F. E. Friedli P. J. Frank 《Journal of the American Oil Chemists' Society》1994,71(7):793-794
A kinetic model for the oxidation of dimethyllaurylamine to its amine oxide with hydrogen peroxide was developed. It is a
second-order reaction where k=.0250, .0079 and .0037 kg per mol/min at 75, 60 and 50°C, respectively. Amine oxides ofN-lauryl morpholine, piperidine and 3-methyl piperidine were synthesized, and their rates of formation were determined. Compared
to dimethyllaurylamine, the piperidines react slower, while the morpholine reaction is much faster. 相似文献
103.
二甲苯氨氧化催化剂的制备研究 总被引:1,自引:0,他引:1
采用不同的载体处理方法和活性组分浸渍条件制备了二甲苯氨氧化反应催化剂,并用沸腾床反应对催化剂性能进行比较研究,得到了较佳的制备方法与条件。 相似文献
104.
R. K. Pinschmidt Jr. L. A. Wasowski G. G. Orphanides K. Yacoub 《Progress in Organic Coatings》1996,27(1-4):209-218
Hydrophobic polymers with adjustable levels of primary amine functionality can be prepared by copolymerization of N-ethenylformamide (NEF) with higher vinyl esters and post hydrolysis of the formamide groups. The resulting polymers can be crosslinked under mild conditions using commercially available crosslinking chemistries. The high intrachain reactivity of the vinylamine group with, for example, neighboring co-polyacrylates and poor copolymerizability with other comonomers, for example, styrene, limits the generality of the approach. Pitfalls and solutions to the preparation of amine functional polymers via this approach are presented. 相似文献
105.
新型可见光敏化引发聚合体系 总被引:1,自引:1,他引:0
应用于可见光聚合的新型光敏化引发体系,是由二类不同的具有给电子作用的胺AH-I、AH-Ⅱ和受电子作用的二芳基碘Weng盐(DPIO)复合组成。AH-Ⅰ类胺,如胺肪族胺和芳香族胺的光吸收在300-400nm以下,很容易和碘Weng盐作用形成电荷转移络合物,使光吸收显著移至可见光区。AH-Ⅱ类胺如N-取代的查耳酮、吗啉酮和芪酮等衍生物,具有很大的共轭结构,并且在可见光区有很高的吸收能力,这些体系在暗处 相似文献
106.
Takizawa K Takahashi A Tokuhashi K Kondo S Sekiya A 《Journal of hazardous materials》2008,155(1-2):144-152
Burning velocity measurements of nitrogen-containing compounds, i.e., ammonia (NH3), methylamine (CH3NH2), ethylamine (C2H5NH2), and propylamine (C3H7NH2), were carried out to assess the flammability of potential natural refrigerants. The spherical-vessel (SV) method was used to measure the burning velocity over a wide range of sample and air concentrations. In addition, flame propagation was directly observed by the schlieren photography method, which showed that the spherical flame model was applicable to flames with a burning velocity higher than approximately 5 cm s−1. For CH3NH2, the nozzle burner method was also used to confirm the validity of the results obtained by closed vessel methods. We obtained maximum burning velocities (Su0,max) of 7.2, 24.7, 26.9, and 28.3 cm s−1 for NH3, CH3NH2, C2H5NH2, and C3H7NH2, respectively. It was noted that the burning velocities of NH3 and CH3NH2 were as high as those of the typical hydrofluorocarbon refrigerants difluoromethane (HFC-32, Su0,max = 6.7 cm s−1) and 1,1-difluoroethane (HFC-152a, Su0,max = 23.6 cm s−1), respectively. The burning velocities were compared with those of the parent alkanes, and it was found that introducing an NH2 group into hydrocarbon molecules decreases their burning velocity. 相似文献
107.
Toshio Fujibayashi Takahisa Kasukawa Kazuyuki Morimoto 《Progress in Organic Coatings》1993,22(1-4):231-244
A non-polyisocyanate resin system that can be applied to cationic electrodeposition (CED) paint has been developed. Most of the compositions of binders currently on the market as CED coatings are composed of modified epoxy resins and blocked polyisocyanates, their crosslinking essentially being polyurethane or polyurea formation. This report deals with a new resin system of which crosslinking is based on a ring-opening/etherification reaction between epoxy groups and hydroxyl groups. The ring-opening addition reaction has very low emissions during the baking process. However, it is difficult to attain a compromise between satisfactory reactivity at elevated temperatures and stability in aqueous composition. By a series of careful investigations, we have established the composition of CED coatings that are sufficiently stable and can be satisfactorily cured. The CED paint formulated on this resin system has such desirable properties as low weight loss upon baking, outstanding weatherability, and excellent chipping resistance. Other characteristics are comparable to existing polyisocyanate based CED coatings. 相似文献
108.
Comparing the compatibility of various functionalized polypropylenes with thermoplastic polyurethane (TPU) 总被引:1,自引:0,他引:1
Three functionalized polypropylenes (PP), a maleated PP (PP-g-MA), primary amine functionalized PP (PP-g-NH2), and secondary amine functionalized PP (PP-g-NHR), were melt blended with a thermoplastic polyurethane (TPU) at different compositions. Compatibility of each functionalized PP with TPU was compared by investigating the binary blends using rheological (mixer torques, dynamic shear rheometry), thermal (dynamic mechanical analysis), mechanical (tensile test), and morphological (scanning electron microscopy with image analysis, particle size analysis) measurements. Compatibility of the three functionalized PP's with TPU is ranked in a decreasing order as follows: PP-g-NHR≥PP-g-NH2?PP-g-MA, which is attributed to higher reactivity of amine (primary and secondary) with urethane linkages. Accordingly, the TPU blends with the two types of amine functionalized PP's exhibited much better synergy, as reflected by much improved mechanical properties including higher tensile strength and ultimate elongation, and finer and more stable morphologies. 相似文献
109.
Synthesis and modification of trifunctional epoxy resin with amine terminated polydimethyl siloxanes for semiconductor encapsulation application 总被引:2,自引:0,他引:2
Epoxy resins based on the triglycidyl ether of tris(hydroxyphenyl)methane (TETM) possess a very high heat distortion temperature and superior thermal oxidative stability over other types of epoxy resins. The high performance trifunctional epoxy resin (TETM) was synthesized by the condensation of a hydroxybenzaldehyde with phenol followed by epoxidation with a halohydrin. The structure of the synthesized TETM was confirmed by infrared (IR), mass spectra (MS), and nuclear magnetic resonance (NMR) spectroscopy. Amine terminated polydimethylsiloxanes (ATPDMS) were used to reduce the stress of trifunctional epoxy resin cured with phenolic novolac resin for electronic encapsulation applications. The dispersed silicone rubbers effectively reduce the stress of cured epoxy resins by reducing the coefficient of thermal expansion (CTE) and flexural modulus, while the glass transition temperature (Tg) is depressed by only a small amount. 相似文献
110.
The foaming tendency of a 30 weight % solution of diethanolamine (DEA) in distilled water was measured over a temperature range of 20-85°C and a pressure range of 1-3 MPa in the presense of a number of contaminants including carboxylic acids, oils, 1-4 bis (2-hydroxyethyl) piperazine (HEP), methanol, iron sulphide, silicone antifoam, etc. The measurements were conducted using a Jerguson high pressure sight glass contained in an air bath. Foaming was measured at gas rates up to 7.5 standard m3/d using air, nitrogen, carbon dioxide, and ethane. One notable observation was that the addition of most of the contaminants commonly identified as foam promoters did not create a foaming system with a clean 30% DEA solution. In fact, the only solutes that produced significant foaming were the carboxylic acids as noted previously in the literature by Pauley et al. (1989). The addition of contaminants to a foaming system did increase foam heights and stability substantially and results are presented for methanol and HEP addition to a foaming system of DEA-carboxylic acid. The effects of temperature, pressure, and gas flow rates on foam heights and foam break times were measured for a number of systems. Foaming was increased by a higher temperature and by higher pressure and was much more pronounced when carbon dioxide or ethane gases were used 相似文献