Effect of hydrolysis on molar mass and thermal properties of poly (ester urethanes)

Poly(2-oxazoline) (POx) matrices in the form of non-woven fibrous mats and three-dimensional moulds were obtained by electrospinning and fused deposition modelling (FDM), respectively. To obtain these materials, poly(2-isopropyl-2-oxazoline) (PiPrOx) and gradient copolymers of 2-isopropyl- with 2-n-propyl-2-oxazoline (P(iPrOx-nPrOx)), with relatively low molar masses and low dispersity values, were processed. The conditions for the electrospinning of POx were optimised for both water and the organic solvent. Also, the FDM conditions for the fabrication of POx multi-layer moulds of cylindrical or cubical shape were optimised. The properties of the POx after electrospinning and extrusion from melt were determined. The molar mass of all (co)poly(2-oxazoline)s did not change after electrospinning. Also, FDM did not influence the molar masses of the (co)polymers; however, the long processing of the material caused degradation and an increase in molar mass dispersity. The thermal properties changed significantly after processing of POx what was monitored by increase in enthalpy of exo- and endothermic peaks in differential scanning calorimetry (DSC) curve. The influence of the processing conditions on the structure and properties of the final material were evaluated having in a mind their potential application as scaffolds.

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Coupling effect of PVDF molar mass and carboxyl content in CNTs on microstructure and thermal properties of CNT/PVDF composites

Materials Research Express ◽

10.1088/2053-1591/aac920 ◽

2018 ◽

Vol 5 (6) ◽

pp. 065031

Author(s):

Run Tian ◽

Yanxia Zhang ◽

Zhipeng Li ◽

Yangyang Huan ◽

Guangfen Li ◽

...

Keyword(s):

Thermal Properties ◽

Molar Mass ◽

Coupling Effect ◽

Carboxyl Content

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The kinetics of poly(butylene succinate) synthesis and the influence of molar mass on its thermal properties

Journal of Applied Polymer Science ◽

10.1002/app.40639 ◽

2014 ◽

Vol 131 (16) ◽

pp. n/a-n/a ◽

Cited By ~ 2

Author(s):

Matthieu Garin ◽

Lan Tighzert ◽

Isabelle Vroman ◽

Sinisa Marinkovic ◽

Boris Estrine

Keyword(s):

Thermal Properties ◽

Molar Mass ◽

Butylene Succinate ◽

Kinetics Of

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Morphology, thermal properties and mechanical relaxations of metallocene syndiotactic polypropylenes

e-Polymers ◽

10.1515/epoly.2012.12.1.507 ◽

2012 ◽

Vol 12 (1) ◽

Author(s):

Ester López Moya ◽

José M. Gómez-Elvira ◽

Rosario Benavente ◽

Ernesto Pérez

Keyword(s):

Thermal Properties ◽

Temperature Gradient ◽

Small Proportion ◽

Molar Mass ◽

Processing Conditions ◽

Syndiotactic Polypropylene ◽

Relative Contribution ◽

Two Samples ◽

Concurrent Processes ◽

Crystallisation Rate

AbstractThe complex polymorphic behaviour of four syndiotactic polypropylene (sPP) samples have been analysed by means of DSC and WAXD techniques. Two samples (sPP1, sPP2) were synthesised via metallocene polymerization by using the ansa-zirconocene Ph2C(Cp)(9-Flu)ZrCl2 as catalyst. Finally, two additional specimens with different molar masses (sPP1-Fr1, sPP1-Fr2) were prepared from the most syndiotactic sPP1 sample by temperature gradient extraction. The WAXD analysis shows that together with the orthorhombic form I, form II can coexist in a variable but small proportion depending on both the chain features and the processing conditions. The relative contribution of the disordered and the ordered types of form I is also dictated by molar mass, configurational microstructure as well as processing conditions. The observed changes in the thermal properties as measured by DSC and in the mechanic-dynamical relaxations of the samples, on slowing the crystallisation rate down, can be rationalised in terms of two concurrent processes, namely the perfection undergone by the crystals and the segregation of the amorphous phase.

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Combination of preparative and two-dimensional chromatographic fractionation with thermal analysis for the branching analysis of polyethylene

Polymer Chemistry ◽

10.1039/c8py00522b ◽

2018 ◽

Vol 9 (22) ◽

pp. 3142-3157 ◽

Cited By ~ 9

Author(s):

Paul S. Eselem Bungu ◽

Kristina Pflug ◽

Harald Pasch

Keyword(s):

Thermal Analysis ◽

Thermal Properties ◽

Molar Mass ◽

Branching Fractions ◽

Two Dimensional ◽

Chromatographic Fractionation

Multiple preparative fractionation of LDPE provides molar mass and branching fractions that are analyzed regarding their thermal properties.

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Influence of molar mass on the thermal properties, conductivity and intermolecular interaction of poly(ethylene oxide) solid polymer electrolytes

Polymer International ◽

10.1002/pi.5322 ◽

2017 ◽

Vol 66 (6) ◽

pp. 830-838 ◽

Cited By ~ 4

Author(s):

Fatin Harun ◽

Chin Han Chan ◽

Tan Winie

Keyword(s):

Thermal Properties ◽

Ethylene Oxide ◽

Intermolecular Interaction ◽

Polymer Electrolytes ◽

Molar Mass ◽

Solid Polymer Electrolytes ◽

Solid Polymer ◽

Poly Ethylene Oxide ◽

Poly Ethylene

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Synthesis and Characterization of Lignin-Based Polyurethane as a Potential Compatibilizer

Indonesian Journal of Chemistry ◽

10.22146/ijc.27176 ◽

2018 ◽

Vol 18 (3) ◽

pp. 390 ◽

Cited By ~ 4

Author(s):

Salma Ilmiati ◽

Jana Hafiza ◽

Jaka Fajar Fatriansyah ◽

Elvi Kustiyah ◽

Mochamad Chalid

Keyword(s):

Molecular Weight ◽

Surface Tension ◽

Thermal Properties ◽

Polyethylene Glycol ◽

Thermal Degradation ◽

Molar Mass ◽

Sessile Drop ◽

Synthesis And Characterization ◽

Hyperbranched Structure

Lignin is one of the most abundant biopolymer on earth. It has polar and non-polar side due to its hyperbranched structure, but the polarity of lignin has a higher tendency than non-polarity. Lignin has potential to be compatibilizer if the portion of non-polar can be increased. This research is focused on investigate the synthesis of lignin-based polyurethane to enhance the portion of non-polarity in lignin. Lignin-based polyurethane was prepared by reacting variation 4,4'-Methylenebis(cyclohexyl isocyanate) (HMDI) and polyethylene glycol (PEG), then lignin was added to the reaction. In this study, the structure of lignin-based polyurethane was confirmed by NMR and FTIR. NMR and FTIR showed that lignin successfully grafted. NMR, also used to investigate the variation molar mass of PEG and isocyanate contents effects to polarity of lignin-based polyurethane. The polarity of lignin-based polyurethane decrease as the composition of HMDI and molecular weight of PEG increase. This result also occurs on the sessile drop test that used to determine surface tension of lignin-based polyurethane. The thermal properties of lignin-based polyurethane also investigate using STA. Based on STA, enhancement of composition of HMDI and PEG increase thermal degradation and resistance of lignin-based polyurethane.

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