Formation of Double Melting Peak of Poly(propylene-co-ethylene-co-1-butene) during the Preexpansion Process for Production of Expanded Polypropylene

Crystallization and melting behavior of Poly(L-lactic acid)(PLLA)/Talc composites with different talc content were investigated in detail. The addition of talc can increase the overall crystallization rate of PLLA, 5%talc makes the melt-crystallization peak temperature of PLLA increase from 96.28 °C to 105.22 °C, and the crystallization enthalpy increases from 1.379 J•g-1to 28.99 J•g-1. The melting behavior of PLLA/5%talc composites at a different heating rate during non-isothermal crystallization at different cooling rate shows that heating rate can affect the melting behavior of PLLA, with increasing of heating rate, the double melting peak degenerates to single melting peak. Melting behavior after isothermal crystallization and after cold isothermal crystallization and hot isothermal crystallization indicates that the double-melting peak of PLLA/5%talc composites results from melting-recrystallization.

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Molecular dynamics of poly(propylene) glycol in nanometer confinements

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:2000754 ◽

2000 ◽

Vol 10 (PR7) ◽

pp. Pr7-271-Pr7-274 ◽

Cited By ~ 6

Author(s):

A. Schönhals ◽

H. Goering ◽

K.-W. Brzezinka ◽

Ch. Schick

Keyword(s):

Molecular Dynamics ◽

Propylene Glycol ◽

Poly Propylene

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Study of Molecular Interaction in Binary Mixtures of Poly (Propylene Glycol) Monobutyl Ether(PPGMBE) 1000 with 2-(Methylamino) Ethanol (MAE) and 1-Butanol using Thermodynamic and 1H NMR Spectroscopy

International Conference on Machine Learning, Electrical and Mechanical Engineering (ICMLEME'2014) Jan. 8-9, 2014 Dubai (UAE) ◽

10.15242/iie.e0114073 ◽

2014 ◽

Keyword(s):

Nmr Spectroscopy ◽

Propylene Glycol ◽

Binary Mixtures ◽

1H Nmr ◽

Molecular Interaction ◽

1H Nmr Spectroscopy ◽

Monobutyl Ether ◽

Glycol Monobutyl Ether ◽

Poly Propylene

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Crystallization of Isotactic Poly(propylene) in Solution as Followed by Slow Calorimetry

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19951905 ◽

1995 ◽

Vol 60 (11) ◽

pp. 1905-1924 ◽

Cited By ~ 4

Author(s):

Hong Phuong-Nguyen ◽

Geneviève Delmas

Keyword(s):

Molecular Weight ◽

Crystal Growth ◽

High Temperature ◽

Heat Of Fusion ◽

Complete Dissolution ◽

Polymer Molecular Weight ◽

Solvent Quality ◽

Temperature Ramp ◽

Poly Propylene

Dissolution, crystallization and second dissolution traces of isotactic poly(propylene) have been obtained in a slow temperature ramp (3 K h-1) with the C80 Setaram calorimeter. Traces of phase-change, in presence of solvent, are comparable to traces without solvent. The change of enthalpy on heating or cooling, ∆Htotal, over the 40-170 °C temperature range, is the sum of two contributions, ∆HDSC and ∆Hnetwork. The change ∆HDSC is the usual heat obtained in a fast temperature ramp and ∆Hnetwork is associated with a physical network whose disordering is slow and subject to superheating due to strain. When dissolution is complete, ∆Htotal is equal to ∆H0, the heat of fusion of perfect crystals. The values of ∆Htota for nascent and recrystallized samples are compared. Dissolution is the tool to evaluate the quality of the crystals. The repartition of ∆Htotal, into the two endotherms, reflects the quality of crystals. The crystals grown more rapidly have a higher fraction of network crystals which are stable at high T in the solvents. A complete dissolution, i.e. a high temperature (170 °C or more) is necessary to obtain good crystals. The effect of concentration, polymer molecular weight and solvent quality on crystal growth is analyzed.

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