This research work is based on the comparison of the mixing phenomena of magnesium-aluminum (MgAl) layered double hydroxides (LDHs) intercalated by dodecylbenzene sulfonate (MgAl-DBS) in poly(lactic acid) (PLA). Two mixing techniques were used to compare the dispersion of LDHs in PLA such as sonication-assisted masterbatch (SAM) melt mixing and direct melting (DM) methods. MgAl LDHs synthesized by the urea hydrolysis method and intercalated with DBS anions using anion exchange reaction and were used in different ratios in PLA (1.25, 2.5, and 5 wt%). MgAl LDHs and their anion intercalation were studied by the X-ray diffraction analysis (XRD) method. Different properties of LDH/PLA composites were compared to analyze the effect of these mixing techniques. Dispersion and exfoliation of LDHs in PLA were investigated by X-ray diffraction analysis (XRD) and transmission electron microscopy (TEM). Influences on the rheological properties were evaluated by analyzing the complex viscosities (*), storage modulus (') and loss modulus ('') by using a rheometer. The thermal properties, thermal stability and effect on crystallinity of composites made with the two mixing techniques were analyzed by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) respectively. The mixing mechanism and amount of MgAl-DBS LDHs have a notable effect on the properties of PLA composites with sonication-assisted masterbatch melt mixing techniques giving better dispersion of LDHs in PLA composites as compared to direct melt mixing.
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http://dx.doi.org/10.1039/c8ra08780f | DOI Listing |
Lab Chip
January 2025
Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China.
In regular biosample cryopreservation operations, dropwise pipetting and continuous swirling are ordinarily needed to prevent cell damage ( sudden osmotic change, toxicity and dissolution heat) caused by the high-concentration cryoprotectant (CPA) addition process. The following CPA removal process after freezing and rewarming also requires multiple sample transfer processes and manual work. In order to optimize the cryopreservation process, especially for trace sample preservation, here we present a microfluidic approach integrating CPA addition, sample storage, CPA removal and sample resuspension processes on a 30 × 30 × 4 mm three-layer chip.
View Article and Find Full Text PDFJ Sep Sci
January 2025
R & D Laboratory, TASNEE Technology and Innovation Centre, Al-Jubail Industrial City, Saudi Arabia.
In this study, a commercially available polypropylene homopolymer (H-PP) was blended with blow molding polyethylene (PE) grade via melt mixing using a compounding machine. The resulting blends were subjected to high-temperature size exclusion chromatography (SEC) analysis, coupled with infrared-5 (IR-5), viscometer (VISCO), and multi-angle laser light scattering (MALS) detectors. The molecular weight (MW) and MW distributions were investigated using SEC, and the exact blend compositions were evaluated using C nuclear magnetic resonance.
View Article and Find Full Text PDFBio Protoc
January 2025
Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, USA.
Histological techniques to study muscle are crucial for assessing skeletal muscle health. To preserve tissue morphology, samples are usually fixed in formaldehyde or cryopreserved immediately after excision from the body. Freezing samples in liquid nitrogen, using isopentane as a mediator for efficient cooling, preserves the tissue in its natural state.
View Article and Find Full Text PDFNanomaterials (Basel)
December 2024
Foundation for Research and Technology-Hellas (FORTH), Institute of Chemical Engineering Sciences (ICE-HT), Stadiou Str., GR-265 04 Rio-Patras, Greece.
This work focuses on the incorporation of 2D carbon nanomaterials, such as graphene oxide (GO), reduced graphene oxide (rGO) and graphene nanoplatelets (GNPs), into polypropylene (PP) via melt mixing. The addition of these 2D carbon nanostructured networks offers a novel approach to enhancing/controlling the water vapor permeable capabilities of PP composite membranes, widely used in industrial applications, such as technical (building roof membranes) or medical (surgical gowns) textiles. The study investigates how the dispersion and concentration of these graphene nanomaterials within the PP matrix influence the microstructure and water vapor permeability (WVP) performance.
View Article and Find Full Text PDFNano Lett
January 2025
Department of Forest Biomaterials, North Carolina State University, Raleigh, North Carolina 27607, United States.
Albeit there is widespread application of thermally conductive polymer composites, one challenge is their typical negative temperature dependence on thermal conductivity (TDTC) due to the mismatch in thermal expansion between the polymer and fillers, creating voids at the interfaces. Inspired by the hierarchical structure of snakeskin, where rigid scales and a soft intergap manage expansion, we designed a segregated structure by coating a high-expansion high impact polystyrene (HIPS)/graphite (Gt) composite with a copper alloy. We hypothesize that the Cu alloy restricts the thermal expansion of HIPS/Gt while forming a pseudoconductive network, enhancing TDTC and thermal conductivity (TC).
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