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International Journal of Biological... Dec 2023Epoxidized soybean oil (ESO) was used as a compatibilizer and blended with polylactic acid (PLA) and polypropylene carbonate (PPC) resin to prepare a series of...
Epoxidized soybean oil (ESO) was used as a compatibilizer and blended with polylactic acid (PLA) and polypropylene carbonate (PPC) resin to prepare a series of PLA/PPC/ESO blends with varying compositions. The influence of the variation in the amount of ESO added to the blend system on the thermal properties, optical properties, rheological properties, mechanical properties, and microscopic morphology of the blends was studied. The research indicates that ESO can react with PLA and PPC to form a chemical bond interface, which improves the compatibility of PLA and PPC to a certain extent. With the increase in the amount of ESO added to the blend (1- 5 phr), the complete decomposition temperature, storage modulus, loss modulus, complex viscosity, notched impact strength, and elongation at break of the blend all show a trend of continuous increase. At the same time, the melt flow rate, light transmittance, and tensile strength of the blend do not show significant fluctuations. When the amount of ESO in the system is 5 phr, compared with the PLA/PPC blend, the notched impact strength and elongation at break of the PLA/PPC/ESO blend increase from 4270.3 J/m, 43.89 % to 8560.4 J/m, 211.28 %, respectively, and its tensile strength and transmittance still remain around 63 MPa, 92 %. This improves the toughness of the blend while maintaining its rigidity, demonstrating excellent mechanical and optical properties. At this time, the microscopic morphology of the fracture surface of the impact sample also shows obvious characteristics of tough fracture. However, when the amount of ESO added to the blend is excessive (6 phr), the compatibility of the blending system decreases, which will degrade the performance of the blending material and ultimately destroy the phase morphology of the blend and reduce its mechanical properties.
Topics: Soybean Oil; Polyesters; Polypropylenes
PubMed: 37832613
DOI: 10.1016/j.ijbiomac.2023.127407 -
Biosensors Dec 2021Biofilms growing on electrodes are the heart piece of bioelectrochemical systems (BES). Moreover, the biofilm morphology is key for the efficient performance of BES and...
Biofilms growing on electrodes are the heart piece of bioelectrochemical systems (BES). Moreover, the biofilm morphology is key for the efficient performance of BES and must be monitored and controlled for a stable operation. For the industrial use of BES (i.e., microbial fuel cells for energy production), monitoring of the biofilm accumulation directly on the electrodes during operation is desirable. In this study a commercially available on-line heat transfer biofilm sensor is applied to a graphite-polypropylene (C-PP) pipe and compared to its standard version where the sensor is applied to a stainless-steel pipe. The aim was to investigate the transferability of the sensor to a carbonaceous material (C-PP), that are preferably used as electrode materials for bioelectrochemical systems, thereby enabling biofilm monitoring directly on the electrode surface. The sensor signal was correlated to the gravimetrically determined biofilm thickness in order to identify the sensitivity of the sensor for the detection and quantification of biofilm on both materials. Results confirmed the transferability of the sensor to the C-PP material, despite the sensor sensitivity being decreased by a factor of approx. 5 compared to the default biofilm sensor applied to a stainless-steel pipe.
Topics: Bioelectric Energy Sources; Biofilms; Electrodes; Graphite; Hot Temperature; Polypropylenes; Stainless Steel
PubMed: 35049646
DOI: 10.3390/bios12010018 -
Neuromodulation : Journal of the... Oct 2021The association of morphine ziconotide or sufentanil ziconotide was used to manage cancer pain. Moving these patients is sometimes difficult. In order to transport these...
BACKGROUND
The association of morphine ziconotide or sufentanil ziconotide was used to manage cancer pain. Moving these patients is sometimes difficult. In order to transport these syringes for pump refilling, it could be interesting to demonstrate the stability of the mixture and so to be able to ensure the best transport conditions of syringes.
MATERIALS AND METHODS
A stability indicating UPLC-DAD method was developed and validated according to the ICH guidelines. Fur mixtures of each association have been stored in 5 ± 3°C and 25 ± 2°C and were evaluated for seven days and compared to the initial observed concentrations.
RESULTS
The stability of these associations was demonstrated at 5°C for seven days thanks to relative concentrations (95% confidence intervals of the mean of three samples) systematically positioned between 95% and 105%. No degradation product was observed during the stability study.
CONCLUSION
This study shows the stability of these association morphine ziconotide or sufentanil ziconotide at 5°C for seven days in polypropylen syringes. This result will allow the transport of the preparation under optimal conditions. Advance preparations for intrathecal pump refills could also be feasible.
Topics: Drug Stability; Humans; Morphine; Polypropylenes; Sufentanil; Syringes; omega-Conotoxins
PubMed: 33095956
DOI: 10.1111/ner.13289 -
Nanoscale Sep 2010We report for the first time an ionic fluid based on hydroxylated fullerenes (fullerols). The ionic fluid was synthesized by neutralizing the fully protonated fullerol...
We report for the first time an ionic fluid based on hydroxylated fullerenes (fullerols). The ionic fluid was synthesized by neutralizing the fully protonated fullerol with an amine terminated polyethylene/polypropylene oxide oligomer (Jeffamine). The ionic fluid was compared to a control synthesized by mixing the partially protonated form (sodium form) of the fullerols with the same oligomeric amine in the same ratio as in the ionic fluids (20 wt% fullerol). In the fullerol fluid the ionic bonding significantly perturbs the thermal transitions and melting/crystallization behavior of the amine. In contrast, both the normalized heat of fusion and crystallization of the amine in the control are similar to those of the neat amine consistent with a physical mixture of the fullerols/amine with minimal interactions. In addition to differences in thermal behavior, the fullerol ionic fluid exhibits a complex viscoelastic behavior intermediate between the neat Jeffamine (liquid-like) and the control (solid-like).
Topics: Amines; Crystallization; Fullerenes; Hydrogen Bonding; Ions; Polyethylene Glycols; Polypropylenes
PubMed: 20820694
DOI: 10.1039/c0nr00307g -
Journal of the Mechanical Behavior of... Feb 2022
Letter to the Editor re Schmidt, U. and D. Taylor (2021). "Erosion of soft tissue by polypropylene mesh products." Journal of the mechanical behavior of biomedical materials115: 104281.
Topics: Polypropylenes; Surgical Mesh
PubMed: 33994153
DOI: 10.1016/j.jmbbm.2021.104546 -
International Journal of Nanomedicine 2020Despite the significant advances in modeling of biomechanical aspects of cell microenvironment, it remains a major challenge to precisely mimic the physiological...
PURPOSE
Despite the significant advances in modeling of biomechanical aspects of cell microenvironment, it remains a major challenge to precisely mimic the physiological condition of the particular cell niche. Here, the metal-organic frameworks (MOFs) have been introduced as a feasible platform for multifactorial control of cell-substrate interaction, given the wide range of physical and mechanical properties of MOF materials and their structural flexibility.
RESULTS
In situ crystallization of zeolitic imidazolate framework-8 (ZIF-8) on the polydopamine (PDA)-modified membrane significantly raised surface energy, wettability, roughness, and stiffness of the substrate. This modulation led to an almost twofold increment in the primary attachment of dental pulp stem cells (DPSCs) compare to conventional plastic culture dishes. The findings indicate that polypropylene (PP) membrane modified by PDA/ZIF-8 coating effectively supports the growth and proliferation of DPSCs at a substantial rate. Further analysis also displayed the exaggerated multilineage differentiation of DPSCs with amplified level of autocrine cell fate determination signals, like , and . Notably, osteogenic markers were dramatically overexpressed (more than 100-folds rather than tissue culture plate) in response to biomechanical characteristics of the ZIF-8 layer.
CONCLUSION
Hence, surface modification of cell culture platforms with MOF nanostructures proposed as a powerful nanomedical approach for selectively guiding stem cells for tissue regeneration. In particular, PP/PDA/ZIF-8 membrane presented ideal characteristics for using as a barrier membrane for guided bone regeneration (GBR) in periodontal tissue engineering.
Topics: Bone Regeneration; Cell Culture Techniques; Cell Differentiation; Guided Tissue Regeneration; Indoles; Membranes, Artificial; Osteogenesis; Polymers; Polypropylenes; Stem Cells; Zeolites
PubMed: 33335393
DOI: 10.2147/IJN.S269169 -
Marine Pollution Bulletin Sep 2016Though plastics show good chemical inertness, they could sorb polychlorinated biphenyls (PCBs) and other toxic pollutants from the surrounding environment. Thus,...
Though plastics show good chemical inertness, they could sorb polychlorinated biphenyls (PCBs) and other toxic pollutants from the surrounding environment. Thus, ingestion of microplastics by marine organisms potentially enhances the transport and bioavailability of toxic chemicals. However, there is lack of studies on the sorption capacity, mechanism and factors affecting the sorption behavior. Here, sorption of PCBs by microplastics in the simulated seawater was studied using the batch oscillation equilibration technique, in which polypropylene (PP) and 3,3',4,4'-tetrachlorobiphenyl (PCB77) acted as model plastic and PCB, respectively. Factors including particle size, temperature and solution environment were investigated. Results showed that, equilibrium sorption time is about 8h and sorption capacity increase with decreasing particle size and temperature. Different sorption capacity in three solution environments was observed. Equilibrium data in three solution environments fitted very well to the Langmuir sorption model, indicating chemical sorption is the predominant mechanism.
Topics: Adsorption; Environmental Monitoring; Models, Theoretical; Particle Size; Plastics; Polychlorinated Biphenyls; Polypropylenes; Seawater; Water Pollutants, Chemical
PubMed: 27230985
DOI: 10.1016/j.marpolbul.2016.05.036 -
ACS Applied Materials & Interfaces Jan 2015Disinfecting, nonbleaching compound 1-chloro-2,2,5,5-tetramethyl-4-imidazolidinone (MC) was uniformly coated onto polypropylene melt-blown nonwoven fabrics having...
Disinfecting, nonbleaching compound 1-chloro-2,2,5,5-tetramethyl-4-imidazolidinone (MC) was uniformly coated onto polypropylene melt-blown nonwoven fabrics having basis-weights of 22 and 50 g/m(2) in order to impart antimicrobial properties via a pad-dry technique. The antimicrobial efficacies of the tested fabrics loaded with MC compound were evaluated against bioaerosols of Staphylococcus aureus and Escherichia coli O157:H7 utilizing a colony counting method. It was determined that both types of coated fabrics exhibited superior antimicrobial efficacy upon exposure to aerosol generation for 3 h. The effect of the coating on air permeability was found to be minimal. Samples were stable for a 6 month time period when they were stored in darkness. However, when the fabrics were exposed to fluorescent light, partial chlorine loss was observed. The MC-coated fabrics exhibited great potential for use in protective face masks and air filters to combat airborne pathogens.
Topics: Air Microbiology; Anti-Bacterial Agents; Bacteria; Disinfectants; Escherichia coli; Polypropylenes; Staphylococcus aureus; Textiles
PubMed: 25587845
DOI: 10.1021/am507329m -
Journal of Biomedical Materials... Oct 2007Hernia repair with prosthetic mesh significantly decreases the rate of recurrence compared with traditional, primary suture repair by reducing the tension on the edges...
Hernia repair with prosthetic mesh significantly decreases the rate of recurrence compared with traditional, primary suture repair by reducing the tension on the edges of the wound. However, there are several complications associated with the use of mesh that may be due to the chronic inflammatory reaction to the mesh or a loss of compliance after degradation of the material. Mesh contraction and migration can also occur, sometimes resulting in a recurrent hernia. Based on the chemical structure of the polypropylene mesh material and the physiological conditions to which it is subjected, it is possible that oxidation is responsible for these changes in material properties. Oxidation would result in surface cracking, decreased melting temperature, loss of mass, and reduced compliance of the material. The objective of this study was to identify physiochemical changes in the surface and bulk properties of explanted polypropylene hernia meshes compared to pristine polypropylene mesh materials. Several characterization techniques were utilized, including scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, and compliance testing. Overall, the results supported our hypothesis that oxidation is involved with the degradation of polypropylene hernia mesh materials.
Topics: Biocompatible Materials; Hernia, Abdominal; Humans; Materials Testing; Oxidation-Reduction; Polypropylenes; Prostheses and Implants; Prosthesis Design; Stress, Mechanical; Surface Properties; Surgical Mesh
PubMed: 17285608
DOI: 10.1002/jbm.b.30764 -
Journal of Separation Science May 2022Reversed phase and size-exclusion chromatography methods are commonly used for protein separations, although they are based on distinctly different principles. Reversed...
Comparison of the separation of proteins of wide-ranging molecular weight via trilobal polypropylene capillary-channeled polymer fiber, commercial superficiously porous, and commercial size exclusion columns.
Reversed phase and size-exclusion chromatography methods are commonly used for protein separations, although they are based on distinctly different principles. Reversed phase methods yield hydrophobicity-based (loosely-termed) separation of proteins on porous supports, but tend to be limited to proteins with modest molecular weights based on mass transfer limitations. Alternatively, size-exclusion provides complementary benefits in the separation of higher mass proteins based on entropic, not enthalpic, processes, but tend to yield limited peak capacities. In this study, microbore columns packed with a novel trilobal polypropylene capillary-channeled polymer fiber were used in a reversed phase modality for the separation of polypeptides and proteins of molecular weights ranging from 1.4 to 660 kDa. Chromatographic parameters including gradient times, flow rates, and trifluoroacetic acid concentrations in the mobile phase were optimized to maximize resolution and throughput. Following optimization, the performance of the trilobal fiber column was compared to two commercial-sourced columns, a superficially porous C4-derivatized silica and size exclusion, both of which are sold specifically for protein separations and operated according to the manufacturer-specified conditions. In comparison to the commercial columns, the fiber-based column yielded better separation performance across the entirety of the suite, at much lower cost and shorter separation times.
Topics: Chromatography, High Pressure Liquid; Molecular Weight; Polymers; Polypropylenes; Porosity; Proteins
PubMed: 35172038
DOI: 10.1002/jssc.202100891