A5083321131- Polymer crystallization and properties
- Polymer Nanocomposites and Properties
- biodegradable polymer synthesis and properties
- Microplastics and Plastic Pollution
- Polymer Science and PVC
- Natural Fiber Reinforced Composites
- Mechanical Behavior of Composites
- Recycling and Waste Management Techniques
- Injection Molding Process and Properties
- Material Properties and Processing
- Additive Manufacturing and 3D Printing Technologies
- Tribology and Wear Analysis
- Ultrasonics and Acoustic Wave Propagation
- Polymer Foaming and Composites
- Polymer Nanocomposite Synthesis and Irradiation
- Corrosion Behavior and Inhibition
- Orthopaedic implants and arthroplasty
- Color Science and Applications
- Polymer composites and self-healing
- Vibration Control and Rheological Fluids
- Environmental Impact and Sustainability
- Academic Research in Diverse Fields
- Chemistry Education and Research
- Transport Systems and Technology
- Cultural Heritage Materials Analysis
Universidade Federal de Campina Grande
2012-2021
Instituto de Tecnologia de Pernambuco
2015
Departamento de Ciência e Tecnologia
2009
Materia (United States)
2009
Universidade Federal da Paraíba
1996-2004
Newcastle University
1995-1997
We studied the crystallization and melting phenomena of poly (3- hydroxybutyrate) (PHB), a biodegradable biocompatible semi-crystalline thermoplastic, obtained from renewable resources. Its high crystallinity motivated several studies on behavior, also ways to increase amorphous polymer fraction. The effect heating cooling rates commercial PHB was investigated by differential scanning calorimetry. Several rates, ranging 2.5 20 °C min–1, were used study phase changes during...
Biochar, a stable carbon(C)-rich material produced via biomass pyrolysis under oxygen-limited conditions, has become topic of increasing scientific interest for its potential to improve soil health and sequester carbon, thereby contributing climate change mitigation. Maize stover, globally abundant often underutilized agricultural byproduct, represents promising feedstock biochar production, facilitating waste reduction improvement. However, deeper understanding the dynamics maize-based in...
Effective management of carbon (C) and nitrogen (N) in agricultural soils is crucial for mitigating greenhouse gas (GHG) emissions, particularly nitrous oxide (N2O) dioxide (CO2). This study investigates innovative dual C N isotope-based methods to explore the mechanisms driving N2O CO2 production their potential mitigation, while maintaining soil fertility. By applying selectively labelled fertilizers with both fractions (15NH4NO3 or NH415NO3) microbial transformations are traced, allowing...
Abstract Injection‐molded talc‐filled polypropylene (PP) composites have been exposed to ultraviolet (UV) radiation in the laboratory for periods up 26 weeks. The extent of chemical degradation has assessed by means Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC), results correlated with mechanical properties. In early stages exposure, photo‐oxidation is faster than unfilled polymer, but this trend reversed exposures longer ∼12 Scanning electron...
Abstract Poly(ethylene terephthalate) (PET) is chemically degraded during processing and/or using by a number of sources including temperature, humidity, and ultraviolet radiation. As consequence, large loss in engineering properties observed when PET products are recycled. To overcome this problem, various types chain extenders were developed an attempt to recover the polymer molecular sizes chemical reactions processing. This work investigates use triphenyl phosphite (TPP) as extender...
The aim of the present work is to evaluate effect NaOH solution as a stress cracking agent on thermal and tensile properties PET PET/ZnO composites. solutions were applied during testing effects monitored by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) actual mechanical properties. rate crystallization was increased when samples exposed NaOH, observed both cold melt crystallization; this possibly due reduction in molar mass molecules caused NaOH. During melting,...
Abstract An investigation was conducted on the effects of photodegradation multilayer films based PET copolymers. The were composed by different layers with PET, PET/PEN, and PET/PEI copolymers a total thickness 23 μm. produced coextrusion followed biaxial orientation in an industrial equipment exposed to ultraviolet radiation laboratory for periods up 600 h. samples investigated FTIR‐ATR, UV/visible spectroscopy, fluorescence size exclusion chromatography, mechanical properties, scanning...
POLYOLEFIN PHOTODEGRADATION WITH NATURAL AND ARTIFICIAL EXPOSURE.Samples of polypropylene (PP) and low-density polyethylene (LDPE) were submitted to ultraviolet radiation, in the natural environment also laboratory.Chemical modifications quantified by carbonyl index (CI), mechanical properties melt flow index.The degradation laboratory was comparatively faster than for both types polymers.The accelerating factor determined various investigated.This parameter, however, showed a large...