scholarly journals Improvement in Mechanical Properties and Heat Resistance of PLLA-b-PEG-b-PLLA by Melt Blending with PDLA-b-PEG-b-PDLA for Potential Use as High-Performance Bioplastics

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Supasin Pasee ◽  
Yodthong Baimark
Keyword(s):  
Mechanical Properties ◽  
Ethylene Glycol ◽  
Heat Resistance ◽  
High Performance ◽  
Melt Processing ◽  
Melt Blending ◽  
Poly Ethylene Glycol ◽  
Scanning Calorimetry ◽  
Blend Films ◽  
Poly Ethylene

Ecofriendly poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide) (PLLA-b-PEG-b-PLLA) are flexible bioplastics. In this work, the blending of poly(D-lactide)-b-poly(ethylene glycol)-b-poly(D-lactide) (PDLA-b-PEG-b-PDLA) with various blend ratios for stereocomplex formation has been proved to be an effective method for improving the mechanical properties and heat resistance of PLLA-b-PEG-b-PLLA films. The PLLA-b-PEG-b-PLLA/PDLA-b-PEG-b-PLDA blend films were prepared by melt blending followed with compression molding. The stereocomplexation of PLLA and PDLA end-blocks were characterized by differential scanning calorimetry and X-ray diffraction (XRD). The content of stereocomplex crystallites of blend films increased with the PDLA-b-PEG-b-PDLA ratio. From XRD, the blend films exhibited only stereocomplex crystallites. The stress and strain at break of blend films obtained from tensile tests were enhanced by melt blending with the PDLA-b-PEG-b-PDLA. The heat resistance of blend films determined from testing of dimensional stability to heat and dynamic mechanical analysis were improved with the PDLA-b-PEG-b-PDLA ratio. The sterecomplex PLLA-b-PEG-b-PLLA/PDL-b-PEG-b-PDLA films prepared by melt processing could be used as flexible and good heat-resistance packaging bioplastics.

Mechanical properties and hydrolytic degradation of methoxy poly(ethylene glycol)-b-poly(DL-lactide-coglycolide- co-ε-caprolactone) diblock copolymer films

e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Nongnit Morakot ◽  
Jirasak Threeprom ◽  
Yodthong Baimark
Keyword(s):  
Mechanical Properties ◽  
Weight Loss ◽  
Ethylene Glycol ◽  
Diblock Copolymers ◽  
Hydrolytic Degradation ◽  
Size Exclusion ◽  
Block Length ◽  
Poly Ethylene Glycol ◽  
Scanning Calorimetry ◽  
Poly Ethylene

AbstractBiodegradable films of methoxy poly(ethylene glycol)-b-poly(DL-lactideco- glycolide-co-ε-caprolactone) diblock copolymers (MPEG-b-PDLLGCL) were prepared by solution casting method. Effects of MPEG block length and DLL:G:CL ratio of the MPEG-b-PDLLGCL films on their mechanical properties and hydrolytic degradation were studied and discussed. It was found that the mechanical properties of films were strongly dependent on glass transition temperatures (Tg) of the diblock copolymers. The hydrolytic degradation was investigated in phosphatebuffered solution at 37°C. The degraded films were characterized using gravimetry (%water uptake and %weight loss), 1H-NMR spectroscopy, differential scanning calorimetry and size exclusion chromatography. The %weight loss of the degraded films increased and molecular weight decreased on increasing the MPEG block length and incorporating the G and CL units, according to their %water uptakes. The MPEG content of the degraded film decreased and the Tg increased with hydrolytic degradation time.

Uniformly Dispersed Poly(ethylene glycol) Functionalized Graphene Oxide/Poly(L-lactic acid) Nanocomposites with Balanced Mechanical Properties

2015 ◽  
Vol 815 ◽  
pp. 583-588
Author(s):  
Zi Jing Zhang ◽  
Yan Ni Zhou ◽  
Huan Liu ◽  
Le Min Zhu ◽  
Zhong Ming Li ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Graphene Oxide ◽  
Lactic Acid ◽  
Ethylene Glycol ◽  
High Performance ◽  
Gravimetric Analysis ◽  
Poly Ethylene Glycol ◽  
Functionalized Graphene Oxide ◽  
Strong Interfacial Interaction ◽  
Poly Ethylene

Balanced mechanical properties are always the goal of high-performance general plastics for engineering purposes. In order to develop uniformly dispersed graphene oxide/poly(L-lactic acid) nanocomposites with balanced mechanical properties, a poly(ethylene glycol) (PEG) grafted graphene oxide was introduced into poly(L-lactic acid) (PLLA) matrix. The PEG grafted graphene oxide (GEG) was confirmed by the results of fourier transform infrared (FTIR) spectra and thermal gravimetric analysis (TGA). Then the mechanical properties of the nanohybrids were measured. The results showed that in contrast to the aggregation of GO, GEG could uniformly disperse in PLLA matrix. An intriguing phenomenon is that thanks to the strong interfacial interaction between GEG and PLLA, it exhibits a substantial enhancement of the elongation at break (EB) as well as a simultaneous improvement of the tensile strength (TS), while the addition of GO decreases the EB of PLLA matrix. This work provides a potential industrialized technique for high-performance PLLA nanocomposites

scholarly journals Controlling surface chemistry and mechanical properties of metal ionogels through Lewis acidity and basicity

2021 ◽  
Vol 9 (8) ◽  
pp. 4679-4686
Author(s):  
Coby J. Clarke ◽  
Richard P. Matthews ◽  
Alex P. S. Brogan ◽  
Jason P. Hallett
Keyword(s):  
Mechanical Properties ◽  
Ionic Liquids ◽  
Ethylene Glycol ◽  
Surface Chemistry ◽  
Lewis Acidity ◽  
Metal Species ◽  
Poly Ethylene Glycol ◽  
Acidity And Basicity ◽  
Poly Ethylene

Gels prepared from metal containing ionic liquids with cross-linked poly(ethylene glycol) have surface compositions and mechanical properties that can be controlled by Lewis basicity and acidity of the metal species.

scholarly journals Tailoring Atomoxetine Release Rate from DLP 3D-Printed Tablets Using Artificial Neural Networks: Influence of Tablet Thickness and Drug Loading

Molecules ◽  
2020 ◽  
Vol 26 (1) ◽  
pp. 111
Author(s):  
Gordana Stanojević ◽  
Djordje Medarević ◽  
Ivana Adamov ◽  
Nikola Pešić ◽  
Jovana Kovačević ◽  
...  
Keyword(s):  
Ethylene Glycol ◽  
Release Rate ◽  
Drug Loading ◽  
Prolonged Release ◽  
Cylindrical Shape ◽  
Poly Ethylene Glycol ◽  
Scanning Calorimetry ◽  
3D Printed ◽  
Artificial Neural ◽  
Poly Ethylene

Various three-dimensional printing (3DP) technologies have been investigated so far in relation to their potential to produce customizable medicines and medical devices. The aim of this study was to examine the possibility of tailoring drug release rates from immediate to prolonged release by varying the tablet thickness and the drug loading, as well as to develop artificial neural network (ANN) predictive models for atomoxetine (ATH) release rate from DLP 3D-printed tablets. Photoreactive mixtures were comprised of poly(ethylene glycol) diacrylate (PEGDA) and poly(ethylene glycol) 400 in a constant ratio of 3:1, water, photoinitiator and ATH as a model drug whose content was varied from 5% to 20% (w/w). Designed 3D models of cylindrical shape tablets were of constant diameter, but different thickness. A series of tablets with doses ranging from 2.06 mg to 37.48 mg, exhibiting immediate- and modified-release profiles were successfully fabricated, confirming the potential of this technology in manufacturing dosage forms on demand, with the possibility to adjust the dose and release behavior by varying drug loading and dimensions of tablets. DSC (differential scanning calorimetry), XRPD (X-ray powder diffraction) and microscopic analysis showed that ATH remained in a crystalline form in tablets, while FTIR spectroscopy confirmed that no interactions occurred between ATH and polymers.

Porous poly(L-lactic acid)/poly(ethylene glycol) blend films

2004 ◽  
Vol 94 (3) ◽  
pp. 965-970 ◽  
Author(s):  
Koji Nakane ◽  
Yoshihiro Hata ◽  
Keisuke Morita ◽  
Takashi Ogihara ◽  
Nobuo Ogata
Keyword(s):  
Lactic Acid ◽  
Ethylene Glycol ◽  
Poly Ethylene Glycol ◽  
Blend Films ◽  
Poly Ethylene ◽  
Porous Poly

scholarly journals High-Performance Resistive Pressure Sensor Based on Elastic Composite Hydrogel of Silver Nanowires and Poly(ethylene glycol)

Micromachines ◽  
2018 ◽  
Vol 9 (9) ◽  
pp. 438 ◽  
Author(s):  
Youngsang Ko ◽  
Dabum Kim ◽  
Goomin Kwon ◽  
Jungmok You
Keyword(s):  
Composite Material ◽  
Ethylene Glycol ◽  
Pressure Sensor ◽  
High Performance ◽  
Silver Nanowires ◽  
High Sensitivity ◽  
Composite Hydrogel ◽  
Poly Ethylene Glycol ◽  
Pressure Sensing ◽  
Poly Ethylene

Improved pressure sensing is of great interest to enable the next-generation of bioelectronics systems. This paper describes the development of a transparent, flexible, highly sensitive pressure sensor, having a composite sandwich structure of elastic silver nanowires (AgNWs) and poly(ethylene glycol) (PEG). A simple PEG photolithography was employed to construct elastic AgNW-PEG composite patterns on flexible polyethylene terephthalate (PET) film. A porous PEG hydrogel structure enabled the use of conductive AgNW patterns while maintaining the elasticity of the composite material, features that are both essential for high-performance pressure sensing. The transparency and electrical properties of AgNW-PEG composite could be precisely controlled by varying the AgNW concentration. An elastic AgNW-PEG composite hydrogel with 0.6 wt % AgNW concentration exhibited high transmittance including T550nm of around 86%, low sheet resistance of 22.69 Ω·sq−1, and excellent bending durability (only 5.8% resistance increase under bending to 10 mm radius). A flexible resistive pressure sensor based on our highly transparent AgNW-PEG composite showed stable and reproducible response, high sensitivity (69.7 kPa−1), low sensing threshold (~2 kPa), and fast response time (20–40 ms), demonstrating the effectiveness of the AgNW-PEG composite material as an elastic conductor.

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