Synthesis, physical properties, and crystallization of optically active poly(L-phenyllactic acid) and poly(L-phenyllactic acid-co-L-lactic acid)

2008 ◽  
Vol 110 (6) ◽  
pp. 3954-3962 ◽  
Author(s):  
Hideto Tsuji ◽  
Hiroshi Matsuoka ◽  
Shinichi Itsuno
Keyword(s):  
Lactic Acid ◽  
Physical Properties ◽  
Optically Active ◽  
Phenyllactic Acid

Synthesis and Properties of Biodegradable Liquid Crystalline Poly(ester-Urethane)s Based on Poly(L-Lactic Acid)

2013 ◽  
Vol 652-654 ◽  
pp. 459-462
Author(s):  
Ya Tong Guo ◽  
Zhu Zheng ◽  
Zhen Qi Hou ◽  
Jie Du
Keyword(s):  
Phase Transition ◽  
Thermal Stability ◽  
Lactic Acid ◽  
Physical Properties ◽  
Liquid Crystalline ◽  
Degradation Rate ◽  
Hydrolytic Degradation ◽  
Hexamethylene Diisocyanate ◽  
Solution Polymerization ◽  
Phase Transition Temperatures

A series of biodegradable segmented liquid crystalline poly(ester-urethane)s were prepared by solution polymerization of poly(L-lactic acid) (PLLA), mesogenic diol prepolymer poly(butylene terephthaloyldioxy dibenzoates) (MD), and hexamethylene diisocyanate (HDI). The MD content was varied from 0 to 40 mol% so that the effects of the mesogen content on the thermal and physical properties, and hydrolytic degradation were examined respectively. It was found that introducing mesogens units could increase the thermal stability and the elastic properties, while reduced the phase transition temperatures and the hydrolytic degradation rate.

Preparation of Poly(Lactic Acid) Acrylate for UV-Curable Coating Applications

2015 ◽  
Vol 659 ◽  
pp. 570-574 ◽  
Author(s):  
Apinya Musidang ◽  
Nantana Jiratumnukul
Keyword(s):  
Lactic Acid ◽  
Physical Properties ◽  
High Efficiency ◽  
Low Energy ◽  
Poly Lactic Acid ◽  
Coating Film ◽  
Pencil Hardness ◽  
Uv Curable ◽  
Low Energy Consumption ◽  
Volatile Organic

UV-curable process is widely used for paints, inks and adhesives due to its rapid curing, low energy consumption, high efficiency and low volatile organic compounds (VOCs). The objective of this research is to prepare poly(lactic acid) (PLA) based UV-curable coating by using glycolyzed PLA. PLA was glycolyzed by ethylene glycol (EG) at 170°C for 90 minutes. The obtained glycolyzed PLA was reacted with methacrylic anhydride (MAAH) to provide PLA acrylate oligomer. The obtained PLA acrylate oligomer was used in coating formulations with various amounts of photoinitiator and cured under UV radiation. Physical properties of cured coating film were investigated such as pencil hardness, gloss and haze. The results showed that poly(lactic acid) (PLA) based UV-curable coating provided good physical properties.

XVIII.—The Physical Properties of Mixed Solutions of Independent Optically - Active Substances

1907 ◽  
Vol 27 ◽  
pp. 172-180
Author(s):  
Clerk Ranken ◽  
W. W. Taylor
Keyword(s):  
Physical Properties ◽  
Active Substance ◽  
Optically Active ◽  
Present Communication ◽  
Points Of Interest ◽  
Systematic Examination ◽  
Mixed Solutions ◽  
Two Systems ◽  
Active Substances ◽  
Optically Active Substances

The two systems containing one of a pair of optically-active stereoisomers and an independent optically-active substance present many points of interest and importance, but have not hitherto been investigated with any degree of completeness. What is known about them may fairly be said to consist of a series of isolated facts. The present communication also contributes a few more isolated observations, and is, in reality, a preliminary to a more systematic examination of the whole subject.

Compatibility and physical properties of poly(lactic acid)/poly(ethylene terephthalate glycol) blends

2012 ◽  
Vol 20 (12) ◽  
pp. 1300-1306 ◽  
Author(s):  
Jun Yong Park ◽  
Sung Yeon Hwang ◽  
Won Jae Yoon ◽  
Eui Sang Yoo ◽  
Seung Soon Im
Keyword(s):  
Lactic Acid ◽  
Physical Properties ◽  
Ethylene Terephthalate ◽  
Poly Lactic Acid ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

scholarly journals UPLC-QTOF-MS/MS and GC-MS Characterization of Phytochemicals in Vegetable Juice Fermented Using Lactic Acid Bacteria from Kimchi and Their Antioxidant Potential

Antioxidants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1761
Author(s):  
Moeun Lee ◽  
Jung Hee Song ◽  
Eun Ji Choi ◽  
Ye-Rang Yun ◽  
Ki Won Lee ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Antioxidant Activities ◽  
Antioxidant Properties ◽  
Total Phenolic ◽  
Phenyllactic Acid ◽  
Antioxidant Power ◽  
Vegetable Juice ◽  
Daucus Carota L ◽  
Ferric Reducing Antioxidant Power

This study aims to investigate fermentative metabolites in probiotic vegetable juice from four crop varieties (Brassica oleracea var. capitata, B. oleracea var. italica, Daucus carota L., and Beta vulgaris) and their antioxidant properties. Vegetable juice was inoculated with two lactic acid bacteria (LAB) (Companilactobacillus allii WiKim39 and Lactococcus lactis WiKim0124) isolated from kimchi and their properties were evaluated using untargeted UPLC-QTOF-MS/MS and GC-MS. The samples were also evaluated for radical (DPPH• and OH•) scavenging activities, lipid peroxidation, and ferric-reducing antioxidant power. The fermented vegetable juices exhibited high antioxidant activities and increased amounts of total phenolic compounds. Fifteen compounds and thirty-two volatiles were identified using UPLC-QTOF-MS/MS and GC-MS, respectively. LAB fermentation significantly increased the contents of d-leucic acid, indole-3-lactic acid, 3-phenyllactic acid, pyroglutamic acid, γ-aminobutyric acid, and gluconic acid. These six metabolites showed a positive correlation with antioxidant properties. Thus, vegetable juices fermented with WiKim39 and WiKim0124 can be considered as novel bioactive health-promoting sources.

scholarly journals Effect of Lactic Acid Content into on during Miconazole Eye Drops to be Used for Infection Preventive

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Yoshimura K ◽  
Inoue Y ◽  
Koizumi A ◽  
Suzuki M ◽  
Itakura S ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Physical Properties ◽  
Acid Content ◽  
Eye Drops ◽  
Lactic Acid Content ◽  
The Stability

Purpose: The aims of this study were to prepare a 0.1% Miconazole (MCZ) eye-drop solution and to evaluate the stability and physical properties of the preparation.

scholarly journals Physical Properties and Non-Isothermal Crystallisation Kinetics of Primary Mechanically Recycled Poly(l-lactic acid) and Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3396
Author(s):  
Luboš Běhálek ◽  
Jan Novák ◽  
Pavel Brdlík ◽  
Martin Borůvka ◽  
Jiří Habr ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Physical Properties ◽  
Structural Changes ◽  
The Other ◽  
Half Time ◽  
Crystallisation Kinetics ◽  
Isothermal Crystallisation ◽  
Melt Crystallisation ◽  
Kinetics Of ◽  
Crystallisation Rate

The physical properties and non-isothermal melt- and cold-crystallisation kinetics of poly (l-lactic acid) (PLLA) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) biobased polymers reprocessed by mechanical milling of moulded specimens and followed injection moulding with up to seven recycling cycles are investigated. Non-isothermal crystallisation kinetics are evaluated by the half-time of crystallisation and a procedure based on the mathematical treatment of DSC cumulative crystallisation curves at their inflection point (Kratochvil-Kelnar method). Thermomechanical recycling of PLLA raised structural changes that resulted in an increase in melt flow properties by up to six times, a decrease in the thermal stability by up to 80 °C, a reduction in the melt half-time crystallisation by up to about 40%, an increase in the melt crystallisation start temperature, and an increase in the maximum melt crystallisation rate (up to 2.7 times). Furthermore, reprocessing after the first recycling cycle caused the elimination of cold crystallisation when cooling at a slow rate. These structural changes also lowered the cold crystallisation temperature without impacting the maximum cold crystallisation rate. The structural changes of reprocessed PHBV had no significant effect on the non-isothermal crystallisation kinetics of this material. Additionally, the thermomechanical behaviour of reprocessed PHBV indicates that the technological waste of this biopolymer is suitable for recycling as a reusable additive to the virgin polymer matrix. In the case of reprocessed PLLA, on the other hand, a significant decrease in tensile and flexural strength (by 22% and 46%, respectively) was detected, which reflected changes within the biobased polymer structure. Apart from the elastic modulus, all the other thermomechanical properties of PLLA dropped down with an increasing level of recycling.

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