Solvent influence on the dilute solution crystallization of polyethylene and polyoxymethylene

Ergoz, E.; Mandelkern, L.

doi:10.1002/pol.1973.130110201

Cited by 15 publications

(2 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…5,6 In reanalyzing the kinetic data, we have taken a reasonable set of values for the nucleation interfacial free energy5,6 and 118.6 ± 2 °C for the equilibrium dissolution temperature of polyethylene in p-xylene. 7 For the fraction previously analyzed, Mw = 3100, MN = 2900, the new results are independent of the value chosen for " and are essentially the same as those originally reported.1 Plots of In G against the required temperature function yield straight lines of increasing slope for 2 = 0.001-0.01. Two intersecting straight lines, which are consistent with a regime I-II transition, result for u2 = 0.05.…”

supporting

confidence: 67%

Equilibrium dissolution temperature of low molecular weight polyethylene fractions in dilute solution [Erratum to document cited in CA110(12):96260y]

Prasad¹,

Mandelkern²

1989

Macromolecules

View full text Add to dashboard Cite

supporting

confidence: 67%

Equilibrium dissolution temperature of low molecular weight polyethylene fractions in dilute solution [Erratum to document cited in CA110(12):96260y]

Prasad¹,

Mandelkern²

1989

Macromolecules

View full text Add to dashboard Cite

“…Degree of Supercooling of the Various LPE Fractions. Several experimental methods have been used to determine the equilibrium dissolution temperature T d °: (a) The dissolution temperature of PE crystals of known lamellar thickness is extrapolated to infinite thickness. ,,− Such a method has been reported not to be sufficiently sensitive to detect the dependence of T d ° on 〈 M n 〉. (b) The dissolution temperature of extended chain crystals has been identified to T d °.…”

Section: Discussionmentioning

confidence: 99%

Lamellar and Crystalline Layer Thickness of Single Crystals of Narrow Molecular Weight Fractions of Linear Polyethylene

et al. 2002

View full text Add to dashboard Cite

The thermal dependence of the lamellar thickness (L p) and the thickness of crystalline layers (Lcryst) of linear polyethylene single crystals has been revisited. LPE fractions with different average molecular weights were crystallized at the same temperatures to avoid the delicate problem of an arbitrary choice of their equilibrium dissolution temperature to calculate their degree of supercooling. This procedure allows direct check of the thicknesses of the crystalline layers dependence on the degree of supercooling. Indeed, the equilibrium melting and dissolution temperatures depend on the average molecular weight. Mats of linear polyethylene single crystals of various narrow molecular weight fractions were obtained from dilute p-xylene solutions. Their lamellar thickness was determined from the SAXS intensity curve. The crystalline layers thickness was calculated from the linear correlation function of the SAXS intensity curves and from the LAM mode frequency of the Raman spectrum. It depends as expected on the crystallization temperature. However, at a given crystallization temperature, both the thicknesses of the lamellae and of the crystalline layers are nearly independent of molecular weight and therefore also of the degree of supercooling estimated from a well-known semiempirical relationship.

show abstract

Supermolecular structures obtained in systems polyethylene–low molecular solvent on cooling

Michailov

Minkova

1983

Acta Polymerica

View full text Add to dashboard Cite

Some peculiarities of the influence of the phase state of systems polyethylenelow molecular solvent on tlie morphology of the supermolecular structure of polyethylene were eslablished. With equal concentrations and almost equal crystallization temperatures it is possible to obtain Iletlritcs a n d banded spherulites depending o n the phase state determined by the phase diagram. I n Systemen aus Polyethylen und niederrnolekularen Losungstti itteln erhaltene ubermolekulare StrukturenEinige Besonderheiten des Einflusses des Phasenzustandes von Systemen aus Polyethylen und niederrnolekularen Losungsmitteln auf die Morphologie der ubermolekularen Struktur des Polyethylens werden dargelegt. Bei gleicher Konzentration und etwa gleichen Kristallisationstemperature11 ist es moglich, in Abhangigkeit von dem durch das Phasendiagramni bestimmten Phasenzustand Hedritc uud gebanderte Spharolithe zu erhalten.

show abstract

Solvent influence on the dilute solution crystallization of polyethylene and polyoxymethylene

Cited by 15 publications

References 18 publications

Equilibrium dissolution temperature of low molecular weight polyethylene fractions in dilute solution [Erratum to document cited in CA110(12):96260y]

Equilibrium dissolution temperature of low molecular weight polyethylene fractions in dilute solution [Erratum to document cited in CA110(12):96260y]

Lamellar and Crystalline Layer Thickness of Single Crystals of Narrow Molecular Weight Fractions of Linear Polyethylene

Supermolecular structures obtained in systems polyethylene–low molecular solvent on cooling

Contact Info

Product

Resources

About