Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Effect of Organo-Modified Nanoclay on the Thermal and Bulk Structural Properties of Poly(3-hydroxybutyrate)-Epoxidized Natural Rubber Blends: Formation of Multi-Components Biobased Nanohybrids.

ABSTRACT: Multi-component nanohybrids comprising of organo-modified montmorillonite (MMT) and immiscible biopolymer blends of poly(3-hydroxybutyrate) (PHB) and epoxidized natural rubber (ENR-50) were prepared by solvent casting technique. The one and three dimensional morphology of PHB/ENR-50/MMT systems were studied using Polarizing Optical Microscopy (POM) and Scanning Electron Microscopy (SEM). Differential scanning calorimetry (DSC) technique was used to evaluate the thermal properties of the nanohybrids. The melting temperature (Tm) and enthalpy of melting (ΔHm) of PHB decrease with respect to the increase in ENR-50 as well as MMT content. The non-isothermal decomposition of the nanohybrids was studied using thermogravimetric (TG-DTG) analysis. FTIR-ATR spectra supported ring opening of the epoxide group via reaction with carboxyl group of PHB and amines of organic modifier. The reaction mechanism towards the formation of the nanohybrids is proposed.

SUBMITTER: Salehabadi A

PROVIDER: S-EPMC5455927 | biostudies-other | 2014 Jun

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

Phthalocyanine blends improve bulk heterojunction solar cells.

Project description:A core phthalocyanine platform allows engineering of the solubility properties the band gap, shifting the maximum absorption toward the red. A simple method for increasing the efficiency of heterojunction solar cells uses a self-organized blend of phthalocyanine chromophores fabricated by solution processing.

| S-EPMC2836723 | biostudies-literature

Biobased Poly(ethylene terephthalate)/Poly(lactic acid) Blends Tailored with Epoxide Compatibilizers.

Project description:To increase the biobased content of poly(ethylene terephthalate) (PET), up to 30 wt % poly(lactic acid) (PLA) was blended with PET using twin-screw compounding and injection molding processes. Multifunctional epoxide compatibilizers including a chain extender and an impact toughening agent were used as blend modifiers to improve the poor mechanical properties of PET/PLA blends. The mechanical and thermodynamic performances were investigated along with the morphological features through scanning electron microscopy, atomic force microscopy, and interfacial tension determination. From rheological and differential scanning calorimetry results, it was observed that the molecular weight of both PET and PLA increased with compatibilizers because of epoxide reactions. The toughening agent, poly(ethylene-n-butylene-acrylate-co-glycidyl methacrylate) (EBA-GMA), provided a 292% increase in impact strength over the blend but reduced modulus by 25%. In contrast, 0.7 phr addition of the chain extender, poly(styrene-acrylic-co-glycidyl methacrylate) (SA-GMA), yielded comparable performance to that of neat PET without sacrificing the tensile and flexural properties. When both compatibilizers were present in the blend, the mechanical properties remained relatively unaltered or decreased with increasing EBA-GMA content. The differences in mechanical performance observed were considered in relation to the strengthening mechanism of the two differing compatibilizers and their effects on the miscibility of the blend.

| S-EPMC6645286 | biostudies-literature

Production of hydrophobic amino acids from biobased resources: wheat gluten and rubber seed proteins.

Project description:Protein hydrolysis enables production of peptides and free amino acids that are suitable for usage in food and feed or can be used as precursors for bulk chemicals. Several essential amino acids for food and feed have hydrophobic side chains; this property may also be exploited for subsequent separation. Here, we present methods for selective production of hydrophobic amino acids from proteins. Selectivity can be achieved by selection of starting material, selection of hydrolysis conditions, and separation of achieved hydrolysate. Several protease combinations were applied for hydrolysis of rubber seed protein concentrate, wheat gluten, and bovine serum albumin (BSA). High degree of hydrolysis (>50 %) could be achieved. Hydrophobic selectivity was influenced by the combination of proteases and by the extent of hydrolysis. Combination of Pronase and Peptidase R showed the highest selectivity towards hydrophobic amino acids, roughly doubling the content of hydrophobic amino acids in the products compared to the original substrates. Hydrophobic selectivity of 0.6 mol-hydrophobic/mol-total free amino acids was observed after 6 h hydrolysis of wheat gluten and 24 h hydrolysis of rubber seed proteins and BSA. The results of experiments with rubber seed proteins and wheat gluten suggest that this process can be applied to agro-industrial residues.

| S-EPMC4989023 | biostudies-literature

Bulk heterojunction morphology of polymer:fullerene blends revealed by ultrafast spectroscopy.

Project description:Morphology of organic photovoltaic bulk heterojunctions (BHJs) - a nanoscale texture of the donor and acceptor phases - is one of the key factors influencing efficiency of organic solar cells. Detailed knowledge of the morphology is hampered by the fact that it is notoriously difficult to investigate by microscopic methods. Here we all-optically track the exciton harvesting dynamics in the fullerene acceptor phase from which subdivision of the fullerene domain sizes into the mixed phase (2-15 nm) and large (>50 nm) domains is readily obtained via the Monte-Carlo simulations. These results were independently confirmed by a combination of X-ray scattering, electron and atomic-force microscopies, and time-resolved photoluminescence spectroscopy. In the large domains, the excitons are lost due to the high energy disorder while in the ordered materials the excitons are harvested with high efficiency even from the domains as large as 100 nm due to the absence of low-energy traps. Therefore, optimizing of blend nanomorphology together with increasing the material order are deemed as winning strategies in the exciton harvesting optimization.

| S-EPMC5099942 | biostudies-literature

Effect of Compatibilization on Biobased Rubber-Toughened Poly(trimethylene terephthalate): Miscibility, Morphology, and Mechanical Properties.

Project description:Fabrication of partially biobased poly(trimethylene terephthalate) (PTT) elastomeric blends was done via melt processing. Both natural rubber (NR) and epoxidized NR (ENR) were investigated as impact modifiers at 40 wt % loading to avoid lowering the overall biobased content of the blend system below that of the PTT alone (35% renewable content), along with maleated polybutadiene rubber (MR) and dicumyl peroxide (DCP) as reactive compatibilizers. The compatibility of the blend components was investigated using contact angle, rheometry, and scanning electron microscopy (SEM). The interfacial tensions and work of adhesions indicated that ENR was more miscible than NR in the PTT blend system, which was corroborated by the higher shear viscosity of the ENR blends and strong shear thinning behavior. Additionally, the predictive modeling of viscosity ratios on the elastomer-thermoplastic morphology was found to match the SEM micrographs with the dispersed elastomeric phase within the PTT matrix. The SEM images of the blends also establish that both the compatibilizers reduced the rubber inclusions size, though DCP hampered the impact performance as compared to the MR. In the presence of the MR, there was an increased cross-linking and observed variation in the Fourier transform infrared peaks demonstrating chemical interactions between the maleic anhydride groups with the PTT that allowed for the impact strength to reach 137 J·m-1 or 4.5 times that of the neat PTT, with the modulus of toughness increased by 82% and an elongation at yield of 50% because of the flexibility and amorphous nature of the rubber constituent.

| S-EPMC6644667 | biostudies-literature

Valorization of Industrial Lignin as Biobased Carbon Source in Fire Retardant System for Polyamide 11 Blends.

Project description:In this study, two different types of industrial lignin (i.e., lignosulphonate lignin (LL) and kraft lignin (DL)) were exploited as charring agents with phosphorus-based flame retardants for polyamide 11 (PA11). The effect of lignins on the thermal stability and fire behavior of PA11 combined with phosphinate additives (namely, aluminum phosphinate (AlP) and zinc phosphinate (ZnP)) has been studied by thermogravimetric analysis (TGA), UL 94 vertical flame spread, and cone calorimetry tests. Various blends of flame retarded PA11 were prepared by melt process using a twin-screw extruder. Thermogravimetric analyses showed that the LL containing ternary blends are able to provide higher thermal stability, as well as a developed char residue. The decomposition of the phosphinates led to the formation of phosphate compounds in the condensed phase, which promotes the formation of a stable char. Flammability tests showed that LL/ZnP ternary blends were able to achieve self-extinction and V-1 classification; the other formulations showed a strong melt dripping and higher burning. In addition to this, cone calorimetry results showed that the most enhanced behavior was found when 10 wt % of LL and AlP were combined, which strongly reduced PHRR (-74%) and THR (-22%), due to the interaction between LL and AlP, which not only promotes char formation but also confers the stability to char in the condensed phase.

| S-EPMC6401932 | biostudies-literature

Harnessing nonlinear rubber swelling for bulk synthesis of anisotropic hybrid nanoparticles.

Project description:Asymmetric hybrid nanoparticles are at the forefront of colloidal chemistry as building blocks for novel structures and applications, as well as for exploring fundamental ways of breaking symmetry in physical systems. Current methods of synthesis have significant limitations in terms of control over synthesis, particle size ranges and polydispersity. We report a facile and scalable synthesis based on the anisotropic swelling of rubber to obtain metal-(polymer rubber) hybrid nanoparticles. Initial Au nanoparticle (NP) seeds are grown larger by reducing HAuCl4 with divinyl benzene (DVB), while simultaneous radical polymerization of DVB forms a cross-linked rubber layer of PDVB on the Au NP surface. The propensity of rubber to swell nonlinearly in the presence of DVB monomers amplifies initial asymmetries to break the symmetry of the PDVB shell, causing growth of asymmetric protrusions on one side of the core-shell particles, which are fixed by further polymerization. Plasmonic absorption of Au allows us to follow the Au reduction reaction and also suggests potential applications of some of the asymmetric particles in plasmon-enhanced sensing. The polydispersity, determined statistically from TEM and SEM images, of the resulting particles is low (<10%) and their sizes, shapes and metal-polymer ratios are easily tunable.

| S-EPMC4894071 | biostudies-literature

The Role of Non-Rubber Components on Molecular Network of Natural Rubber during Accelerated Storage.

Project description:Though the non-rubber components have long been recognized to be a vital factor affecting the network of natural rubber (NR), the authentic role of non-rubber components on the network during accelerated storage has not been fully illuminated. This work attempts to clarify the impact of non-rubber components on the network for NR during accelerated storage. A natural network model for NR was proposed based on the gel content, crosslinking density, and the non-rubber components distribution for NR before and after centrifugation. Furthermore, the effect of non-rubber components on the network was investigated during accelerated storage. The results show that terminal crosslinking induced by non-rubber components and entanglements are primary factors affecting the network formation during accelerated storage. By applying the tube model to analyze the stress-strain curves of NR, we found that the contribution of the entanglements to the network formation is larger than that of terminal crosslinking during accelerated storage. The work highlights the role of non-rubber components on the network during accelerated storage, which is essential for understanding the storage hardening mechanism of NR.

| S-EPMC7760701 | biostudies-literature

Fabrication of novel strain sensors from green TPV nanocomposites based on poly(3-hydroxybutyrate-<i>co</i>-3-hydroxyvalerate) (PHBV)/silicone rubber/silicon-modified graphene oxide.

Project description:In this study, a new thermoplastic vulcanizate (TPV) blend of silicone rubber (SR) and poly (3-hydroxybutyrate-co-3-hydroxy valerate) (PHBV) including silicon-modified graphene oxide (SMGO), is used to fabricate highly flexible and sensitive strain sensors. The sensors are built with an extremely low percolation threshold of 1.3 vol%. We investigated the effect of adding SMGO nanoparticles to strain-sensing applications. The findings demonstrated that increasing the SMGO concentration enhanced the composite's mechanical, rheological, morphological, dynamic mechanical, electrical, and strain-sensing capabilities. But too many SMGO particles can reduce elasticity and cause nanoparticle aggregation. The nanocomposite's gauge factor (GF) values were discovered to be 375, 163, and 38, with nanofiller contents of 5.0 wt%, 3.0 wt%, and 1.0 wt% respectively. Cyclic strain-sensing behavior showed their ability to recognize and classify various motions. Due to its superior strain-sensing capabilities, TPV5 was chosen to assess the repeatability and stability of this material when utilized as a strain sensor. The sensor's excellent stretchability, sensitivity (GF = 375), and remarkable repeatability during cyclic tensile testing allowed them to be stretched beyond 100% of the applied strain. This study offers a new and valuable method for building conductive networks in polymer composites, with potential uses in strain sensing, especially in biomedical applications. The study also emphasizes the potential of SMGO as a conductive filler for developing extremely sensitive and flexible TPEs with enhanced, environmentally friendly features.

| S-EPMC10262175 | biostudies-literature

Photo-derived transformation from modified chitosan@calcium carbonate nanohybrids to nanosponges.

Project description:Zwitterionic chitosan (ZC)@calcium carbonate (CC) nanoparticles were conveniently obtained and transformed to biocompatible nanosponges by continuous gas-phase photo-derived transformation in a single-pass configuration, and their potential use for biomedical applications was investigated. The mean diameter of the ZC@CC sponges was ~166?nm (~72?nm for CC and, ~171?nm for ZC), and the sponges had a mesoporous structure (i.e., an average pore diameter of ~13?nm). Measurements of the sponge cytotoxicity were performed and only a slight decrease was observed (>78% in cell viability) when compared with pure ZC (>80%). The ZC@CC sponges had a similar transfection ability to lipofectamine (~2.7?×?10(9) RLU mg(-1) protein) at a 50:1 ratio of sponge:DNA weight. Because of a porous structure, the sponges showed remarkably higher transfection efficiencies than pure ZC.

| S-EPMC4919630 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data