bluuebunny/crossref_metadata_2025_split huggingface dataset:
Processing of boron filament wound composites
Authors: Juneau P. W. , Saffire V. N. , Hug D. P. , Golliday D. 
Published: December 2004

AbstractBoron fiber reinforced composites have been extensively evaluated in epoxy resin matrix materials, which are satisfactory for applications in comparatively moderate environments, and are usually inapplicable at temperatures in excess of 400°F. For use in high temperature environments in excess of this figure, it is necessary to use more thermally stable resins. A modified phenolic resin was selected for this application because of the versatility of the material and the successful performance of phenolics in glass fiber reinforced structures. The modifications increased the viscosity and tack of the formulation so that consolidation could not be readily accomplished by a combination of tension and heat during the winding process, so that a multi‐stage winding process with intermediate consolidation steps became necessary. Winding a complex path to make a uniformly thick wall on a frustrum required further modifications to the basic winding process. The successful solution of these problems and the development of structurally sound composites was the primary object of this work.
Differential thermal analysis using high frequency dielectric heating I. Theory and equipment
Authors: Wald S. A. , Winding C. C. 
Published: December 2004

AbstractA new analytical technique, differential thermal analysis using high frequency dielectric heating (DTA/HF), has been developed which senses the rate and extent of the enthalpy change accompanying curing. These two parameters relate simply and quantitatively to curing reaction kinetics.In DTA/HF cylindrical samples of uncured elastomers, 2‐in. in diam and about 1‐in. high, enclosed in glass rings and covered, are heated in a high frequency (86 mc) electrical field simultaneously with an identically‐shaped precured reference disc of the same elastomer. Both sample and reference are clamped securely between 3 × 5‐in. rectangular output electrodes. The sample is cured isometrically under pressure generated by thermal expansion. Temperatures at the core of the sample and reference are monitored continuously using ungrounded junction thermocouples with stainless steel probes; both sample temperature and temperature differences between sample and reference are recorded.To test the validity of DTA/HF it was first applied to the dicumyl peroxide (DCP) curing of several cis‐1,4‐polyisoprene calcium carbonate mixtures for which reaction mechanisms and reaction kinetic data are available.
Differential thermal analysis using high frequency dielectric heating III. A mathematical model for predicting radial temperature gradients in the dielectric heating of polymers
Authors: Wald S. A. , Winding C. C. 
Published: December 2004

AbstractA mathematical model has been developed to predict radial temperature gradients in polymers during dielectric heating. The time‐temperature model includes parameters for rate of dielectric heating, thermal conductivity, density, heat capacity, surface coefficient of heat transfer, and sample radius. The application of this model was checked experimentally on a 2‐in. cylinder of cured polyisoprene.
The polymer‐forming reactions of 3,3,3‐trichloropropylene oxide
Authors: Vogt H. C. , Davis P. 
Published: December 2004

Abstract3,3,3‐Trichloropropylene oxide (TCPO) is a monomer which has the combination of a highly reactive epoxide group and a stable trichloromethyl group. The epoxy group will undergo ring opening polymerizations with itself and with a host of other compounds to yield polymeric materials. Water, alcohols, phenols, amines, carboxylic acids and many other compounds react with TCPO with the aid of Lewis acid type catalysts. The electron‐withdrawing influence of the trichloromethyl group, steric effects and the oxirane ring have a strong influence on the course of reactions, which are often radically different from that encountered with the simpler alkylene oxide monomers.
A theoretical melting model for a reciprocating‐screw injection molding machine
Authors: Donovan R. C. 
Published: December 2004

AbstractA theoretical model for the transient melting behavior in a reciprocating‐screw injection molding machine is proposed. The model is based on a steady state extrusion model, Neumann's melting problem, and a heuristic postulate for the transient behavior. The model predictions are compared to experimental melting data for low density polyethylene, acrylonitrile‐butadiene‐styrene polymers and polyvinyl chloride for a variety of operating conditions and two screw designs. A useful degree of correlation is demonstrated for all experimental cases.
Processing conditions and properties of semicrystalline polymers, I: Effect of mechanical properties of a chlorinated polyether
Authors: Collier J. R. , Cruz‐Saenz A. R. , Gentile W. , Dinos N. 
Published: December 2004

AbstractControlled changes in crystallization conditions and shear history prior to and following both extrusion and compression molding were shown to drastically alter the mechanical properties of the polymer studied. This material, Poly[3,3‐(bischloromethyl) oxacyclobutane], is an essentially linear polymer with a number average molecular weight of 300,000. The effect of heat transfer, as limited by experimental conditions, had a primary influence upon the crystallization phenomenon and therefore also upon the morphology and the resultant mechanical properties.By proper selection of processing conditions it was possible to alter the mechanical properties of this polymer from brittle behavior to the ability to form a neck and draw to high degrees of elongation. Using conditions that imparted the ability to neck and draw, it was shown that this process is sensitive to both strain rate during testing and extrusion rate during processing. The underlying cause of the effects upon mechanical properties appear to be the dramatic changes occurring in morphology as a result of the selected processing conditions.A chemical etching agent was used on these samples prior to replication, and observation in the electron microscope. Using this technique the internal morphology was studied and compared to the surface morphology. There was not a gradient of morphology in these samples. Furthermore, the use of this etching agent that attacked non‐crystalline regions preferentially, suggested that the lamellar fine structure of spherulites is composed of smaller units.
Solids conveying in screw extruders part I: A modified isothermal model
Authors: Broyer E. , Tadmor Z. 
Published: December 2004

AbstractAn improved theoretical model was derived for the solids conveying zone of a plasticating extruder. The model makes possible calculations in variable channel depth section. It also allows for a bulk density which is a function of pressure and for the non‐isotropic pressure distribution in the solid plug. An expression for maximum flow rate was also derived. Results simulated by the model on a computer indicate the effect of variables on extruder performance. The power consumption terms in the solids conveying zone of a plasticating extruder were also derived. Total power consumption is the sum of power consumptions on the barrel surface, screw surfaces and those due to pressure rise. Their relative importance was analyzed by computations. The effect of operating conditions and coefficients of friction on the various power terms was also analyzed.
Mechanical properties of mixtures of two compatible polymers
Authors: Yee A. F. 
Published: December 2004

AbstractThe properties of mixtures of poly(2, 6‐dimethyl p‐phenylene oxide) and poly(styrene) have been measured by DSC, density gradient, dynamic mechanical response, and tensile testing. The mixtures are found to have single glass trasitions that vary continuously with the composition. They also have small negative excess volumes of mixing, indicative of strong polymerpolymer interaction. The dynamic mechanical response of the mixtures shows that the low temperature secondary relaxations are suppressed whereas those at high temperatures are enhanced. These observations imply that mixing on the segmental levc l has occurred. A plot of tensile strength vs composition at different strain rates reveals two regions of failure behavior. The high PS, high strain rate region is brittle, and the high PM2PO, low strain rate region is ductile. When the tensile yield data are treated according to the Ree‐Eyring equation, the addition of PS to PM2PO is found to reduce the flow volum, e of the mixture. The overall effect on mechanical properties of adding small amounts of one component to the other is similar to that of anti‐plasticization. Our experimental observations are consistent with the shifting of the relaxation mechanisms to longer times due to the negative excess volume of mixing.
Using the SI units
Authors: Conant F. S. 
Published: December 2004

AbstractSI surpasses previous metric systems in coherence, simplicity, distinction between force and mass, choice of units, and uniformity of usage. Coherence eliminates conversion factors, other than powers of ten, within the system. Through simplification, only seven base units, two supplementary units, seventeen named derived units, and sixteen prefixes are needed to describe the entire system. Promotion of the newton as a unit of force and retention of the kilogram for mass clarifies the difference between the two quantities. New units are: pascal for pressure, siemens for electric conductance, and mole for amount of a substance. International agreement minimizes proliferation of specialized units or usage. Adopted conventions include spelling, abbreviations, style, and usage, as well as definitions for the units. Toleranceg, rounding of numbers, and elimination of the comma in multidigit numbers assume new significance. Conversion to SI offers a unique opportunity to reduce the number of sizes of many products. Several schemes for metric modularism have been developed for this purpose. In changing from conventional tip SI units, the key idea is “think metric” rather than use dual dimensioning.
Effects of orientation and chemical structure on the strength properties of some polymers
Authors: Takano Masaharu , Nielsen Lawrence E. 
Published: December 2004

AbstractThe stress‐strain properties of oriented polymers are measured parallel and perpendicular to the direction of hot stretching. The polymers include styrene‐acrylonitrile copolymers, vinyl alcohol copolymers, acrylic acid copolymers, polyelecf trolytes, and a high density polyethylene. Polarity and hydrogen bonding tend to increase the strength, especially in the direction perpendicular to the direction of hot stretching. Strong electrostatic bonding in polyelectrolytes and too much polar bonding in styrene‐acrylonitrile & polymers decrease the strength by reducing the molecular mobility, which is required to prevent brittleness.
Castor oil based interpenetrating polymer networks. II. Synthesis and properties of emulsion polymerized products
Authors: Devia‐Manjarres N. , Conde A. , Yenwo G. , Pulido J. , Manson J. A. , Sperling L. H. 
Published: December 2004

AbstractPolystyrene Latexes were synthesized using sodium ricinoleate (the ehief saponification product of castor oil) as the surfactant. Later sulfur, more sodium ricinoleate, and sometimes castor oil were added, and the emulsion heated to a temperature where the sulfur vulcanized the castor oil products, making a semi‐interpenetrating polymer network. Stress‐strain studies showed the presence of a well developed yield point and high elongation for some samples, indicating considerable toughening for slow rates of strain. Electron microscopy revealed a complex two‐phased morphology. Usually polystyrene was the continuous phase. The rubbery phase domain size depended upon the amount of castor oil products added lzod impact strengths showed only modest improvements; probably because of the high glass transition temperature of the castor oil vulcanizate.
Integral‐skin polyurethane foams
Authors: Marciano J. H. , Reboredo M. M. , Rojas A. J. , Williams R. J. J. 
Published: December 2004

AbstractA model describing the expansion of a polyurethane (PU) foam in a closed mold is developed. An energy balance is stated, together with constitutive equations for the vaporization rate of the foaming agent and the polymerization kinetics. A numerical solution is obtained for an experimentally‐characterized PU formulation. It is shown that in order to avoid premature gelling or undesirable density distributions, the wall temperature must be close to the initial one. The relative fraction of skin in the foam may be increased by decreasing the part thickness or by adding less catalyst or more blowing agent to the formulation. Factors affecting cream, rise, and process times are discussed.
The synthesis and cationic polymerization of novel epoxide monomers
Authors: Crivello James V. 
Published: December 2004

AbstractThe preparation of a novel series of multifunctional silicon‐containing epoxide monomers, oligomers, and polymers has been carried out. The hydrosilylation method employed was found to be applicable to the design and synthesis of a wide variety of materials with different chemical and mechanical characteristics, which range from hard and brittle to elastomeric. By tailoring the kinds of and number of epoxide groups that are incorporated into these materials, it is possible to substantially modify their reactivity in photoinitiated cationic polymerization. Those monomers and oligomers containing cycloaliphatic epoxide rings undergo polymerization rates considerably more rapid than conventional epoxides. There are many applications of such photocurable monomers in the field of electronic materials.
Effect of post‐exposure delay in positive acting chemically amplified resists: An analytical study
Authors: Nalamasu O. , Reichmanis E. , Hanson J. E. , Kanga R. S. , Heimbrook L. A. , Emerson A. B. , Baiocchi F. A. , Vaidya S. 
Published: December 2004

AbstractThe lithographic performance of chemically amplified positive resists depends on controlling the delay time between the exposure and post‐exposure bake (PEB) process steps. The effect of post‐exposure delay (PED) was investigated in poly(t‐butoxycarbonyloxystyrene‐sulfone) formulated with photoacid generators (PAG) by a variety of analytical techniques including Rutherford backscattering, infrared, X‐ray photoelectron and laser ablation microprobe mass spectrometry. The results indicate that the base‐insoluble residue formed during PED is primarily a surface phenomenon and is a result of incomplete deprotection at the resist surface. It was determined that ppb levels of basic vapors present in the resist processing environment affect process performance profoundly by reacting with the photogenerated acids during PED. Isolation of resist surface from the immediate environment by means of a thin, acidic, and base‐soluble overcoat (covercoat) material dramatically alleviates the environmental effects by quenching basic airborne contaminants and improves PED latitude.
Novel auto‐photosensitive polyimides with tailored properties
Authors: Rohde Ottmar , Smolka Paul , Falcigno Pasquale A. , Pfeifer Josef 
Published: December 2004

AbstractAn overview is given on auto‐photosensitive polyimides as introduced for the first time in 1985. It is shown how development proceeded and how the chemical basis of auto‐photosensitive polyimides was extended beyond BTDA. Novel “photosensitizer tetracarboxylic dianhydrides” like 2,3,6,7‐thioxanthonetetracarboxylic dianhydride (TXDA) were synthesized and copolymerized into preimidized nonphotoactive polyimides containing tetracarboxylic acids like 6FDA or ODPA. Novel photosensitive polyimides were obtained that carry all essential features of BTDA based systems plus higher photospeed. They provide the ability to better tailor material properties to specific applications.
Einwirkung von Aethylendiamin auf Nitrophenole, deren Aether und corresp. Halogenverbindungen
Authors: Jedlicka K. 
Published: December 2004

AbstractZweck der Untersuchung war zu ermitteln: ob Aethylendiamin auf Nitrophenole, deren Methyläther und entsprechende Halogennitrobenzole in analoger Weise wie das Ammoniak einwirke.
Berlinerblau und Turnbullsblau. I
Authors: Müller Erich , Stanisch Theophil 
Published: December 2004

AbstractDie beim Vermischen der Lösungen von Ferrichlorid und Ferrocyankalium andrerseits und vom Ferrochlorid und Ferricyankalium anderseits sich bildenden blauen Verbindungen sind sämtlich Ferrocyanide.
Über die Arachinsäure, die Isobehensäure und die normale Eikosansäure
Authors: Ehrenstein R. , Stuewer H. 
Published: December 2004

Abstract1. Die aus dem Erdnußöl zu gewinnende Arachinsäure ist nicht die normale Eikoansäure CH3(CH2)18COOH, sondern eine Isodokosansäure C21H43COOH, also eine Säure mit verzweigter Kette.
Über die Azide der organischen Basen
Authors: Cīrulis A. , Straumanis M. 
Published: December 2004

AbstractEs wurden die Darstellungsmethoden und Eigenschaften folgender 21 neuer Verbindungen von organischen Basen mit Stickstoffwasserstoffsäure beschrieben:

Nr.
Verbindung
Schmp. °C
Nr.
Verbindung
Schmp. °C

1
Äthylaminazid
65
11
Di‐isoamylaminazid
176

2
n‐Propylaminazid
verflüchtigt sich
12
Äthylendiaminazid
172

13
Propylendiaminazid
166

3
n‐Buthylaminazid
85
14
Diamidopropanolazid
115

4
Isobuthylaminazid
115
15
Guanidinazid
46

5
Allylaminazid
verflüchtigt
16
Amidoguanidinazid
123

17
Benzylaminazid
157

6
Dimethylaminazid
74
18
Piperidinazid
60

7
Diäthylaminazid
48
19
Amidocyclohexanazid
112–113

8
Di‐n‐propylaminazid
101
20
Piperazinazid
180–181

9
Di‐n‐buthylaminazid
143
21
„Nitronazid”︁
160

10
Di‐isobuthylaminazid
135

Alle diese Verbindungen sind krystalline Stoffe, meistens weiß und können nicht als Sprengstoffe betrachtet werden.
Über die thermische Zersetzung von Natriumsulfat
Authors: Leibnitz E. , Tittel M. 
Published: December 2004

AbstractReines Na2SO4 wird im Pt‐Tiegel auch bei 1350° noch nicht zersetzt. Dagegen zeigt es einen der Oberfläche der Schmelze offensichtlich proportionalen beträchtlichen Verdampfungsverlust.
Darstellung Selenorganischer Verbindungen in wäßrigem Medium
Authors: Funk Herbert , Papenroth Wolfgang 
Published: December 2004

AbstractEs werden Umsetzungen ungesättigter aliphatischer Kohlenwasserstoffe mit Selendioxyd und Chlorwasserstoff‐ bzw. Bromwasserstoffsäure in wäßrigem Medium beschrieben.
Über die Synthese von 1,3,4‐Thiadiazolidinen und 1,3,4‐Thiadiazolen
Authors: Rühlmann Klaus 
Published: December 2004

AbstractEs wird die Darstellung symmetrischer 1,3,4‐Thiadiazolidine aus aliphatischen Aldehyden und cycloaliphatischen Ketonen durch gleichzeitige Einwirkung von H2S und wäßrigem Hydrazinhydrat mitgeteilt. Die in 2‐ und 5‐Stellung monosubstituierten 1,3,4‐Thiadiazolidine lassen sich mit elementarem Schwefel bei höheren Temperaturen in Gegenwart von Piperidin zu Thiadiazolen dehydrieren. Beim Erhitzen mit Piperidin allein werden unter H2S‐Abspaltung Aldazine oder Ketazine gebildet. Durch saure Hydrolyse werden die 1,3,4‐Thiadiazolidine gespalten in H2S, Hydrazin und Carbonylverbindungen, gegenüber wäßrigem Alkali hingegen erweisen sie sich als bemerkenswert beständig.
Racematspaltung von Aminosäureamiden und ‐hydraziden
Authors: Losse Günter , Hebel Hans‐Joachim , Kästner Christa 
Published: December 2004

AbstractD, L‐Aminosäureamide und ‐hydrazide bilden mit Weinsäurederivaten wie Dibenzoyl‐D‐weinsäure diastereomere Tartrate, die sich sehr gut zur Trennung in die optischen Antipoden eignen. Die Anwendung dieser Methode wird an mehreren Beispielen erläutert.
Über die Darstellung von 2‐Alkoxy‐3‐methoxyphenolen aus o‐Vanillin und über Mannichsynthesen mit diesen Pyrogalloläthern
Authors: Profft Elmar , Rietz Gerhard 
Published: December 2004

AbstractDurch Oxydation mit Perameisensäure in 85proz. Ameisensäure konnten Äther des o‐Vanillins in 70–75proz. Ausbeuten zu den entsprechenden 2‐Alkoxy‐3‐methoxyphenolen abgebaut werden. Bei solchen o‐Vanillinäthern, die sich nicht oder nur sehr schlecht in der Ameisensäure lösen, versagt die Methode. Die dargestellten 2‐Alkoxy‐3‐methoxyphenole wurden als Benzoyl‐ und 3,5‐Dinitrobenzoylverbindungen als Kohlensäureester und als Äther charakterisiert.Mit einigen dieser Pyrogallol‐di‐äther wurden Kondensationen nach Mannich durchgeführt, wobei in Ausbeuten um 50% und mehr 2‐Alkoxy‐3‐methoxy‐6‐piperidino‐N‐methylenphenole entstanden. Von diesen erwies sich das Hydrochlorid des 2‐i‐Amyläthers in seiner oberflächenanästhetischen Wirkung als etwas stärker als Cocain.
Grenzflächenaktive Polyhydroxylverbindungen. VIII. N‐n‐Alkylcarbaminsäure‐β‐D‐glucopyranosyl‐ester (1) der Kettenlänge C8C12
Authors: Bertsch H. , Ulsperger E. , Gerhardt W. 
Published: December 2004

AbstractEs werden die Darstellung und die Eigenschaften von N‐n‐Alkylcarbaminsäure‐β‐D‐glucopyranosyl‐estern (1) der Kettenlänge C8C12 beschrieben.
Synthese mit Isocyanaten I. Umsetzung von N‐Dimethylformamid mit Phenyl‐ und α‐Naphthylisocyanat
Authors: Jovtscheff A. , Falk F. 
Published: December 2004

AbstractEs wird über eine Darstellung von N‐Aryl‐N′, N′‐dimethylformamidinen aus Arylisocyanaten und N‐Dimethylformamid berichtet.
Über bi‐ und polycyclische Azulene. IL. Heterocyclisch anellierte Azazulene
Authors: Treibs Wilhelm , Poppe Ernst‐Joachim 
Published: December 2004

AbstractDie Darstellung von Azazulenen, an die ein Benzthiazol oder Benzselenazol anelliert ist, gelingt durch Dehydrierung der aus Suberon und heterocyclischen Hydrazinen durch Indolsynthese erhaltenen Heptindole mittels Chloranil.
Grundlagen zur Aromaten‐Extraktion mit Alkylformamiden. I. Phasengleichgewichtsbestimmungen im Quaternären System Benzol—n‐Heptan—Dimethylformamid—Wasser
Authors: Steib Hellmut 
Published: December 2004

AbstractDas System Benzol—n‐Heptan—Dimethylformamid—Wasser wird als ein Beispiel für ein quaternäres System ausgemessen, bei welchem drei von den sechs darin enthaltenen binären Systemen nur teilweise ineinander löslich sind. Es werden die Löslichkeitsgrenzen für die vier im Gesamtsystem enthaltenen ternären Systeme und für einige charakteristische Vierstoffgemischkombinationen bestimmt und daraus für Temperaturen von 20°, 40° und 60°C die Binodalkurven gefunden. Für einige dieser Systeme und Kombinationen werden eine Anzahl Konoden bestimmt und auf ihre Gesetzmäßigkeiten, Verteilungskoeffizienten und Selektivitätswerte untersucht. Diese Untersuchungen beziehen sich in der Hauptsache auf die bei 20°C vorliegenden Bedingungen, in einem Falle auch auf die bei 40°C vorliegenden.Die Darstellung der Ergebnisse erfolgt in Form von Gibbsschen Dreiecken, einem daraus aufgebauten Tetraeder und einem rechtwinkligen Selektivitätsdiagramm. Der Umfang der Untersuchungen wurde so abgemessen, daß durch Interpolationen und Extrapolationen zwischen den erhaltenen Werten eine für theoretische und praktische Untersuchungen ausreichende Vorstellung des Gesamtsystems gewonnen werden kann.