| A New Readily Processable Polyimide, |
OCT 1986 |
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| Authors:
F. W. Harris; M. W. Beltz; P. M. Hergenrother
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 | As part of an effort to develop tough solvent resistance thermoplastics for potential use as structural resins on aerospace vehicles, a new processable polyimide was evaluated. Various physical properties such as thermal stability, solvent resistance, glass transition temperature, crystalline melt temperature, melt viscosity; and mechanical properties such as fracture toughness, adhesive, film and composite properties are reported. Of particular interest is the extremely high titanium to titanium tensile shear strength ... |
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| New Polyarylene Ethers, |
OCT 1986 |
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| Authors:
P. M. Hergenrother; S. J. Havens; B. J. Jensen
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| As part of an effort to develop improved composite matrices for potential use on aerospace vehicles, a series of new polyarylene ethers (PAEs) were prepared from the reaction of activated dihalo compounds with various bisphenols. Measured number average molecular weights for the PAEs ranged from 13,500 to 39,400 g/mole, and glass transition temperatures varied from 152 to 280 degrees C. Ethynyl-terminated polyarylene ethers (ETPAEs were also prepared by endcapping hydroxy ... |
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| Thermoplastic Composite Matrices with Improved Solvent Resistance, |
03 APR 1984 |
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| Authors:
P. M. Hergenrother; B. J. Jensen; S. J. Havens
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| Aromatic thermoplastics such as polyarylene ether sulfones and polyethersulfones are excellent engineering resins with good thermoformability and mechanical properties. However, they exhibit pronounced sensitivity (especially while under stress) towards certain solvents. As a result, these materials are unacceptable for use as matrices in composite structures on aerospace vehicles where resistance to hydraulic fluids and paint strippers is an important requirement. As part of a NASA program to develop new concepts ... |
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| Solvent Resistant Thermoplastic Composite Matrices, |
1984 |
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| Authors:
P. M. Hergenrother; B. J. Jensen; S. J. Havens
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| Thermoplastics (e.g. polysulfones) as structural resin (e.g. adhesives and composite matrices) are sensitive to aircraft fluids (e.g. hydraulic fluid and paint stripper) and, upon exposure, undergo a loss of mechanical properties, especially in a stressed condition. Various molecular substitution approaches were used to develop new concepts and technology that improve the solvent resistance of termoplastics without severely compromising the attractive features such as toughness and thermoformability. Thermoplastics were modified with ... |
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| Polyphenyl-as-triazines and polyphenylquinoxalines, new high performance polymers. |
APR 74 |
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| Authors:
P. M. Hergenrother; BOEING AEROSPACE CO SEATTLE WASH
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| Polyphenyl-as-triazines and polyphenylquinoxalines are high tem- perature thermoplastics which exhibit excellent potential for use as functional and structural resins in environments which demand high chemical and thermal stability. These polymers are prepared in soluble high molecular weight forms and exhibit good processability with the evolution of little or no volatiles. Potential areas of application include use as protective coatings, adhesives, and composite matrices. (Author-PL) |
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| Polyphenylquinoxalines: SYNTHESIS, CHARACTERIZATION, AND MECHANICAL PROPERTIES. |
APR 73 |
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| Authors:
P. M. Hergenrother; BOEING CO SEATTLE WASH
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| The synthesis of polyphenylquinoxalines (PPQ) is discussed in detail. Solu-tions of PPQ at 20% solids content from stoichiometric quantities of reactants are generally metastable, increasing in viscosity and in some cases, gelling. This can be alleviated without any appreciable detrimental effect upon the polymer by upsetting the stoichiometry of the reactants. Relatively high molecular weight polymer (inherent viscosity = 1.84) can be obtained when the stoichiometry is upset by 2%. ... |
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| DEVELOPMENT OF POLYPHENYLQUINOXALINE GRAPHITE COMPOSITES |
JAN 73 |
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| Authors:
J. T. Hoggatt; P. M. Hergenrother; J. G. Shdo; BOEING AEROSPACE CO SEATTLE WASH
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| DEVELOPMENT OF POLYPHENYLQUINOXALINE GRAPHITE COMPOSITES. |
JAN 73 |
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| Authors:
J. T. Hoggatt; P. M. Hergenrother; J. G. Shdo; BOEING CO SEATTLE WASH
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| The potential of polyphenylquinoxaline (PPQ)/ graphite composites to serve as structural material at 316 C (600 F) has been demonstrated using a block copolymer, PPQ DERIVATIVE. Thirteen polyphenylquinoxalines were evaluated. Four candidate polymers were selected for preliminary evaluation as matrices for HMS graphite fiber reinforced composites. The preliminary composite evaluation enabled selection of one of the four polymers for advanced composite preparation and testing. Using an experimentally established cure schedule ... |
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| Development of Polyphenylquinoxaline Graphite Composites |
JAN 73 |
141 pages |
| Authors:
J. T. Hoggatt; P. M. Hergenrother; J. G. Shdo; BOEING CO SEATTLE WA
|
 | The potential of polyphenylquinoxaline (PPQ)/graphite composites to serve as structural material at 316 deg C (600 deg F) has been demonstrated using a block copolymer, BlCo(l :3), PPQ derivative. Initially, thirteen polyphenylquinoxalines were evaluated. From this work, four candidate polymers were selected for preliminary evaluation as matrices for HMS graphite fiber reinforced composites. The preliminary composite evaluation enabled selection of one of the four polymers for advanced composite preparation and ... |
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| Phenylquinoxaline copolymers. |
NOV 72 |
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| Authors:
P. M. Hergenrother; BOEING CO SEATTLE WASH
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| Phenylquinoxaline homopolymers consisting of low, intermediate, and high molecular weight versions were prepared from the reaction of 3,3'- diaminobenzidine (DAB) and 3,3', 4,4'-tetraaminobenzophenone (TAB), each with p- bis )phenylglyoxalyl9 benzene as solutions (18% solids contest) in a 1:1 mixture of m-cresol and sylene. Three random and three block copolymers were also prepared from DAB and TAB with p-bis (phenylglyoxalyl) benzene. Both metastable and stable solutions of high molecular weight polymers ... |
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| Poly-as-triazines from oxalamidrazone. |
AUG 72 |
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| Authors:
P. M. Hergenrother; BOEING CO SEATTLE WASH
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| The preparation of asymmetrical-triazine polymers from the reaction of oxalamidrazone with various aromatic bisglyoxals and dibenzils is described. This study was performed to determine the effect two as- triazine rings adjacent to each other in the backbone of the polymer chain have upon the overall properties of the polymer and to determine if these polymers exhibited any unique properties as structural or functional resins. (P.S.-PL) ANNOTATION: Synthesis of polytriazines from ... |
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| Polyquinazolotriazoles, |
MAR 1971 |
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| Authors:
P. M. Hergenrother; BOEING SCIENTIFIC RESEARCH LABS SEATTLE WASH
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| A novel high molecular weight (eta(inh) = 1.4 dl/g) polyquinazolotriazole (PQT) was prepared from the reaction of 3,3'-(2'',6''-pyridinediyl)bis(5-(o-aminophenyl)-1,2,4-triazole) with isophthalic acid by solution cyclopolycondensation in polyphosphoric acid, with diphenyl isophthalate by melt polycondensation, and with isophthaloyl chloride to form a precursor polyamide which subsequently underway cyclodehydration. Thermal characterization of the PQT by TGA showed initial weight loss in air commencing at about 490C. The PQT exhibited a weight loss of ... |
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| POLYPHENYL-as-TRIAZINES, |
AUG 1970 |
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| Authors:
P. M. Hergenrother; D. E. Kiyohara; BOEING SCIENTIFIC RESEARCH LABS SEATTLE WASH
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| The report discusses the synthesis and uses of poly-as-triazines. Poly-as-triazines can be synthesized in high molecular weights while retaining processability and solubility in certain organic solvents. Consequently they can be processed into potentially useful high temperature adhesives, laminating resins, protective coatings, and films. Preliminaryevaluations have hown considerable promise along these lines. The poly-as-triazines exhibit slightly better thermal stability in air than in an inert atmosphere. This is an usual phenomenon ... |
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| THERMAL ANALYSIS OF A POLYPHENYL-as-TRIAZINE, |
JUN 1970 |
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| Authors:
W. J. Wrasidlo; P. M. Hergenrother; BOEING SCIENTIFIC RESEARCH LABS SEATTLE WASH
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| A well-characterized poly(phenyl-as-triazine) was pyrolysed under dynamic and isothermal conditions in vacuum and in air. Simultaneous thermogravimetric, differential thermal and thermobarometric analysis of polymer films indicate a multistage thermal decomposition. An exothermic reaction between 305 and 465C was shown to involve the asymmetric triazine ring. This leads to the formation of a stable intermediate symmetrical triazine and nitrilic products, primarily benzonitrile. Based on the data, a degradation scheme initially involving ... |
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| POLYQUINOXALINES CONTAINING p-PHENYLENE ETHER AND p-PHENYLENE MOIETIES, |
APR 1970 |
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| Authors:
P. M. Hergenrother; D. E. Kiyohara; BOEING SCIENTIFIC RESEARCH LABS SEATTLE WASH
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| A series of quinoxaline polymers containing p-phenylene ether and p-phenylene moieties were prepared by polymerization of 3,3-diaminobenzidine with various aromatic bisglyoxals in m-cresol. The glass transition temperature (Tg) of the polyquinoxalines varied from 133C for a polymer highest in p-phenylene ether content to 350C for a polymer containing rigid p-phenylene moieties. Although thermalgravimetric analysis failed to show any distinct difference between the p-phenylene ether and the p-phenylene polymers, isothermal weight ... |
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| POLYQUINOXALINES A. SYNTHESIS AND PRELIMINARY MECHANICAL PROPERTIES AS LAMINATING AND ADHESIVE RESINS, |
OCT 1968 |
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| Authors:
P. M. Hergenrother; H. H. Levine; BOEING SCIENTIFIC RESEARCH LABS SEATTLE WASH POLYMER SCIENCES LAB
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| A study on polyquinoxalines synthesis was conducted which provided a method of obtaining processable, reproducible high molecular weight polymers as solutions in m-cresol; these solutions had excellent storageability at ambient temperatures. Polyquinoxaline solutions in m-cresol were readily used for prepreg and tape preparation. Laminate and adhesive data showed the excellent potential of the polyquinoxalines for high temperature applications. (Author) |
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| High-temperature structural resins. |
MAY 65 |
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| Authors:
P. M. Hergenrother; G. Johnston Jr.; H. H. Levine; WHITTAKER CORP SAN DIEGO CALIF NARMCO RESEARCH AND DEVELOPMENT DIV
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| Polyimides, polybenzothiazoles, and polyquinoxalines continue to display excellent hydrolytic, oxidative and thermal stability. Preliminary application work indicated the potential of these systems as structural adhesives and laminating resins. Preliminary 14-ply polyimide laminates and 7- ply polyquinoxaline laminates gave maximum room temperature flexural strengths of 91,690 psi and 114,300 psi, and moduli of 4.42 x 10 to the 6th power psi and 4.06 x 10 to the 6th power psi respectively. ... |
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| Synthesis of Polythiazoles and Polyfluoroolefins, |
AUG 1962 |
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| Authors:
P. E. Brumfield ; A. V. DiGiulio ; A. Lebovits ; P. M. Hergenrother
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| The synthesis of organic polymers of high thermal stability is reported. Two approaches were followed: the condensation polymerization of a chain of aromatic nuclei joined through heterocyclic groups, and the polymerization of fluoroolefins containing heterocyclics groups to give fluorocarbon polymers with pendant heterocyclic substituents. In a preliminary study, eight model thiazole compounds with aryl substituents were prepared and compared as to thermal stability as a guide to designing polymer chains. ... |
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Reports by Author
