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Selected Works

1975

Articles 1 - 7 of 7

Full-Text Articles in Engineering

Poly(Alkyl Alpha-Chloroacrylates). Iv. Tacticity Analysis From 300 Mhz Proton Magnetic Resonance Spectra.Pdf, William Macknight, G. R. Dever, F. E. Karasz, R. W. Lenz Dec 1974

Poly(Alkyl Alpha-Chloroacrylates). Iv. Tacticity Analysis From 300 Mhz Proton Magnetic Resonance Spectra.Pdf, William Macknight, G. R. Dever, F. E. Karasz, R. W. Lenz

William MacKnight

300 MHz proton magnetic resonance spectroscopy was applied to the determination of triad structures of three poly(alkyl a-chloroacrylates) of widely varying stereoregularities. Assign­ments and quantitative analyses were made for all of the tetrad peaks in the backbone methylene resonance of poly(methyl a-chloroacrylate), poly(ethyl a-chloroacrylate), and poly(isopropyl a­chloroacrylate). In addition the methyl singlet peaks of poly(methyl a-chloroacrylate), the methyl triplet peaks of poly(ethyl a-chloroacrylate) which had not been amenable previously to resolution at 220 MHz, and the methyl doublet peaks of poly(isopropyl a-chloroacrylate) were resolved, and the triad values which were obtained from these pendant ester group resonances compared favorably with …

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Relaxations In Cyano-Substitued Polypentenamers And Their Hydrogenated Derivatives, William Macknight, R. Neumann, K. Sanui Dec 1974

Relaxations In Cyano-Substitued Polypentenamers And Their Hydrogenated Derivatives, William Macknight, R. Neumann, K. Sanui

William MacKnight

Two series of cyano-substituted polypentenamers and ·their hydrogenated derivatives have been studied by dynamic mechanical and dielectric relaxation in the temperature range from -160 to 110°C and at frequencies from 3.5 Hz to 10 kHz. Series I contains 7.4 mol % cyano groups and series II contains 20 mol % cyano groups. The amorphous cyanopolypentenamers display one major mechanical and dielectric relaxation region asso­ciated with motions accompanying the glass transition and labeled /3. A small secondary relaxation, labeled 'Y, is also discernible in the mechanical E" results. The semicrystalline hydrogenated derivatives exhibit three relaxation regions labeled a, /3, and 'Y …

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Structure And Properties Of The System: Poly(2, 6-Dimethyl-Phenylene Oxide) Isotactic Polystyrene. Wide-Angle X-Ray Studies, William Macknight, R. Hammel, F. E. Karasz Dec 1974

Structure And Properties Of The System: Poly(2, 6-Dimethyl-Phenylene Oxide) Isotactic Polystyrene. Wide-Angle X-Ray Studies, William Macknight, R. Hammel, F. E. Karasz

William MacKnight

No abstract provided.

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Preparation Of Brominated Polypentenamer And Its Substituted Nitrile Derivative, William Macknight, F. E. Karasz, J. R. Fried Dec 1974

Preparation Of Brominated Polypentenamer And Its Substituted Nitrile Derivative, William Macknight, F. E. Karasz, J. R. Fried

William MacKnight

No abstract provided.

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Poly(Alkyl Alpha-Chloroacrylates). Vi. Transitions And Relaxations.Pdf, William Macknight, G. R. Dever, F. E. Karasz, R. W. Lenz Dec 1974

Poly(Alkyl Alpha-Chloroacrylates). Vi. Transitions And Relaxations.Pdf, William Macknight, G. R. Dever, F. E. Karasz, R. W. Lenz

William MacKnight

Melting points (Tm's) and glass transition temperatures (Tg's) of stereoregular poly(methyl a-chlo­roacrylates), poly(ethyl a-chloroacrylates), and poly(isopropyl a-chloroacrylates) have been determined by differ­ential scanning calorimetry (DSC). Relaxation processes accompanying these Tg's and secondary relaxation phe­nomena have been studied by dynamic mechanical and dielectric relaxation. It was found that the extrapolated Tg values for high molecular weight syndiotactic poly(alkyl a-chloroacrylates) and high molecular weight isotactic po­ly(alkyl a-chloroacrylates) differed by the following amounts: 92° for the methyl esters; 83° for the ethyl esters; and 68° for the isopropyl esters. A secondary relaxation, labeled fl, and associated with motions of the ester side chains, …

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Structure And Properties Of The System: Poly(2, 6-Dimethyl-Phenylene Oxide) Isotactic Polystyrene. Small-Angle X-Ray Studies, William Macknight, W. Wenig, F. E. Karasz Dec 1974

Structure And Properties Of The System: Poly(2, 6-Dimethyl-Phenylene Oxide) Isotactic Polystyrene. Small-Angle X-Ray Studies, William Macknight, W. Wenig, F. E. Karasz

William MacKnight

No abstract provided.

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Poly(Alkyl Alpha-Chloroacrylates). V. Preparation And Properties Of Methyl, Ethyl, And Isopropyl Polymers Of Varied Tacticity, William Macknight, G. R. Dever, F. E. Karasz, R. W. Lenz Dec 1974

Poly(Alkyl Alpha-Chloroacrylates). V. Preparation And Properties Of Methyl, Ethyl, And Isopropyl Polymers Of Varied Tacticity, William Macknight, G. R. Dever, F. E. Karasz, R. W. Lenz

William MacKnight

No abstract provided.

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