Polylactide/organically modified montmorillonite composites; effects of organic modifier on thermal characteristics

Ozdemir, Esra
Öztürk, Yurdagül
Hacaloğlu, Jale
The effects of interspace distance and the possible chemical interactions between PLA and the organic modifier of montmorillonites, Cloisite 15A, 20A and 30B on thermal degradation of PLA in the absence and presence of water vapor were investigated by direct pyrolysis mass spectrometry, (DP-MS) in addition to XRD, TEM, DSC, TGA analyses. The DP-MS results clearly showed that the way in which the polymer was incorporated into the nanocomposite strongly depends on the mixing technique, the interspacing between the clay layers and mostly on the type of the organic modifier used. Strong evidences for interactions of the organic modifier of Cloisite 30B with PLA chains resulting in exfoliated structure were detected. In the presence of water vapor, the relative yields of products due to transesterification and cis-elimination reactions were diniinished. Thermal degradation of PLA nano composites was shifted to low temperatures as the partial pressure of H2O was increased.


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Kaya, Hatice; Hacaloğlu, Jale (2014-01-01)
Thermal degradation of polystyrene (PS) involving brominated polyepoxy (BA) and antimony oxide (PS/BE/Sb2O3) was studied systematically via direct pyrolysis mass spectrometry. Thermal decomposition of brominated polyepoxy was started by loss of end groups. The relative yields of high mass thermal degradation products of PS and the product distribution of brominated polyepoxy and antimony oxide were changed noticeably during the pyrolysis of PS/BE/Sb2O3 composite. Its thermal decomposition was initiated by t...
Polylactide/organically modified montmorillonite composite fibers
Ozdemir, Esra; Hacaloğlu, Jale (2017-03-01)
Direct pyrolysis mass spectrometry technique was applied to investigate the characteristics of polylactide, (PLA) nanofibers containing organically modified montmorillonites, Cloisite 15A, (C15A) Cloisite 20A, (C20A) and Cloisite 30B, (GOB) prepared by electrospinning. As the amount of Cloisite present in the composites was increased, the fiber diameters became slightly narrower compared to neat PLA fiber due to the presence of quaternary ammonium salt as organic modifier increasing electrical conductivity....
Thermal degradation characteristics of polysulfones with benzoxazine end groups
Orhan, Tugba; Ates, Sahin; Hacaloğlu, Jale; Yagci, Yusuf (2012-01-01)
Thermal degradation behaviors of phenol and benzoxazine end-capped polysulfone macromonomers (PSU-OH and PSU-P-a) and pre-cured PSU-P-a in the absence and presence of aniline and phenol based benzoxazine monomer (P-a) were investigated via pyrolysis mass spectrometry. A significant increase in thermal stability of both polysulfone and polybenzoxazine chains upon polymerization of benzoxazine end groups was determined compared to phenol-ended polysulfones and aniline based monofunctional polybenzoxazine. The...
Thermal decomposition of glycidyl azide polymer by direct insertion probe mass spectrometry
Fazlioǧlu, Hatice; Hacaloğlu, Jale (2002-01-01)
Thermal decomposition reactions and products of glycidyl azide polymer (GAP), have been investigated by direct insertion mass spectrometry and evolved gas analyses by FTIR spectroscopy techniques. It has been observed that thermal degradation of GAP begins with cleavage of the side groups. Although the main decomposition started with the elimination of molecular nitrogen from the azide functional group, degradation initiated by loss of N-3 and CH2N3, depolymerization type reactions were also identified. Rea...
Thermal degradation of polystyrene composites. Part II. The effect of nanoclay
KAYA, Hatice; Kaynak, Cevdet; Hacaloğlu, Jale (2016-07-01)
In this work, thermal degradation behavior polystyrene/organoclay nanocomposites containing tribromophenol end-capped brominated epoxy oligomer, (BE) with or without Sb2O3 were investigated systematically via direct pyrolysis mass spectrometry. Incorporation of organically modified montmorillonite into polystyrene, (PS) matrix not only increased thermal stability but also the probability of radical recombination, disproportionation and carbonization reactions causing increase in the char yield. Exfoliation ...
Citation Formats
E. Ozdemir, Y. Öztürk, and J. Hacaloğlu, “Polylactide/organically modified montmorillonite composites; effects of organic modifier on thermal characteristics,” POLYMER DEGRADATION AND STABILITY, pp. 87–96, 2016, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/31400.