Synthesis of biorenewable and water-degradable polylactam esters from itaconic acid

2016 ◽  
Vol 18 (15) ◽  
pp. 4170-4175 ◽  
Author(s):  
Pengxu Qi ◽  
Hsiao-Li Chen ◽  
Ha Thi Hoang Nguyen ◽  
Chu-Chieh Lin ◽  
Stephen A. Miller
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Polylactic Acid ◽  
Itaconic Acid ◽  
Main Chain ◽  
Lactam Ring ◽  
One Year ◽  
Chain Ester

Polylactam esters are readily made from biobased itaconic acid and are compared to polylactic acid. The lactam ring improves the glass transition temperature and the main-chain ester groups are more readily hydrolyzed, degrading fully via agitation in water for one year.

The Effect of Methylene Diphenyl Diisocyanate on the Nonisothermal Properties of Polylactic Acid/Elaeis guineensis Fibres Biocomposites

2013 ◽  
Vol 594-595 ◽  
pp. 823-827
Author(s):  
Luqman Hakim Ahmad Subri ◽  
Sakinah Mohd Alauddin ◽  
Senawi Rosman
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Polylactic Acid ◽  
Elaeis Guineensis ◽  
Fibre Surface ◽  
Degree Of Crystallinity ◽  
Chain Mobility ◽  
Methylene Diphenyl Diisocyanate ◽  
The Degree Of Crystallinity

Biocomposites demands are significantly rising due to environmental regulations and concerns. However, incompatibility between the fibre and matrix is a major setback that diminishes the biocompostie properties. Therefore in this work, methylene diphenyl diisocynate (MDI) compatibilizers were used together with fibre surface treatment in order to increase compatibility between polylactic acid (PLA) and Elaeis Guineensis Fibres (EGF) biocomposite. Nonisothermal properties were investigated and it was found that, MDI increased compatibility of the PLA and EGF which led to the restriction of chain movements in the biocomposite. This restriction in chain mobility caused an increase the glass transition temperature and crystallization temperature and also reduced the degree of crystallinity.

scholarly journals Preparation and Characterization of Bletilla striata Polysaccharide/Polylactic Acid Composite

Molecules ◽  
2019 ◽  
Vol 24 (11) ◽  
pp. 2104
Author(s):  
Renyu Yang ◽  
Dongyue Wang ◽  
Hongli Li ◽  
Yi He ◽  
Xiangyu Zheng ◽  
...  
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Composite Film ◽  
Polylactic Acid ◽  
Tensile Tests ◽  
High Price ◽  
Film Material ◽  
Bletilla Striata ◽  
Good Thermal Stability

Polylactic acid (PLA) is limited in its application due to its high price, high brittleness and low glass-transition temperature. Modification methods are currently used to overcome these shortcomings. In this study, Bletilla striata polysaccharide (BSP) was blended with PLA by a solvent method. DMA data showed that the BSP/PLA film had a higher glass-transition temperature, and the glass-transition temperature of the film showed an extreme value of 68 °C when the proportion of the chalk polysaccharide was 0.8%. TG data indicates that the composite film material has good thermal stability. Tensile tests show that the composite film is improved in rigidity and elasticity compared to the pure PLA film. The blending modification of PLA with white peony polysaccharide not only reduces the cost of PLA, but also improves the thermal and mechanical properties of PLA.

scholarly journals Thermal Insulation and Mechanical Properties of Polylactic Acid (PLA) at Different Processing Conditions

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2091
Author(s):  
Mohamed Saeed Barkhad ◽  
Basim Abu-Jdayil ◽  
Abdel Hamid I. Mourad ◽  
Muhammad Z. Iqbal
Keyword(s):  
Thermal Conductivity ◽  
Compressive Strength ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Polylactic Acid ◽  
Thermal Insulation ◽  
Annealing Time ◽  
Insulation Material ◽  
Thermal Insulation Material

This work aims to provide an extensive evaluation on the use of polylactic acid (PLA) as a green, biodegradable thermal insulation material. The PLA was processed by melt extrusion followed by compression molding and then subjected to different annealing conditions. Afterwards, the thermal insulation properties and structural capacity of the PLA were characterized. Increasing the annealing time of PLA in the range of 0–24 h led to a considerable increase in the degree of crystallization, which had a direct impact on the thermal conductivity, density, and glass transition temperature. The thermal conductivity of PLA increased from 0.0643 W/(m·K) for quickly-cooled samples to 0.0904 W/(m·K) for the samples annealed for 24 h, while the glass transition temperature increased by approximately 11.33% to reach 59.0 °C. Moreover, the annealing process substantially improved the compressive strength and rigidity of the PLA and reduced its ductility. The results revealed that annealing PLA for 1–3 h at 90 °C produces an optimum thermal insulation material. The low thermal conductivity (0.0798–0.0865 W/(m·K)), low density (~1233 kg/m3), very low water retention (<0.19%) and high compressive strength (97.2–98.7 MPa) in this annealing time range are very promising to introduce PLA as a green insulation material.

Polyimides Containing 1,3,4-Oxadiazole Rings

2008 ◽  
Vol 73 (12) ◽  
pp. 1631-1644 ◽  
Author(s):  
Maria Bruma ◽  
Mariana-Dana Damaceanu
Keyword(s):  
Thermal Stability ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Main Chain ◽  
The Other ◽  
Carbonyl Groups ◽  
Aromatic Diamines ◽  
Film Forming ◽  
As Solubility

Two series of polyimides containing 1,3,4-oxadiazole rings in the main chain, one of them having flexible hexafluoropropane-2,2-diyl groups and the other with carbonyl groups, were prepared by polycondensation of aromatic diamines containing 1,3,4-oxadiazole rings with hexafluoropropane-2,2-diyl-bis(phthalic anhydride) or benzophenonetetracarboxylic dianhydride. Their properties, such as solubility in organic solvents, thermal stability, glass transition temperature, photoluminescence and film-forming properties of the two groups of polymers have been studied and compared.

The Microstructural Deformation of the Montmorillonite Particles/Polypropylene/Polylactic Acid Nanocomposite Filaments Infused with Plasma Treated Montmorillonite

2009 ◽  
Vol 620-622 ◽  
pp. 469-472 ◽  
Author(s):  
Hai Yan Zhu ◽  
Ying Chen Zhang ◽  
Jing Zou ◽  
Hong Yan Wu ◽  
Y.P. Qiu
Keyword(s):  
Plastic Deformation ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Polylactic Acid ◽  
Dislocation Motion ◽  
Deformation Mechanisms ◽  
Dsc Analysis ◽  
Macromolecular Chain ◽  
Microstructural Deformation

The purpose of the present work is to investigate the microstructural deformation of the montmorillonite (MMT) particles/polypropylene (PP)/polylactic acid (PLA) nanocomposite filaments infused with plasma treated MMT. The activation volumes of the MMT/PP/PLA nanocomposite filaments ranging from 31.4572 to 151.2100 (nm)3 estimated by the Eyring’s equation quantitatively revealed that the plasma treated MMT acted as obstacles to dislocation motion during microstructural plastic deformation mechanisms. DSC analysis showed marked increases in glass transition temperature (Tg), indicating the plasma treated MMT could effectively help resist the free crankshaft movement of the macromolecular chain in the nanocomposite filaments. In addition, the MMT/PP/PLA nanocomposite filaments developed intercalated structures which had been examined by SEM.

Sign in / Sign up

Export Citation Format

Share Document