A clearer understanding of the dynamic structuring of different natural rubber genotypes on a macroscopic and mesoscopic scale by asymmetrical-flow field-flow fractionation (A4F) analysis
IF 5 2区 材料科学Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING
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引用次数: 0
Abstract
Unlike synthetic elastomers, the structure of natural rubber (NR) evolves (dynamic structuring) and so do its properties during the storage before reaching an industrial mixer. In the rubber industry this is known as storage hardening. NR samples from three genotypes (GT1, RRIM600 and PB235) were subjected to different levels of structuring by varying the structuring time (t) on phosphorus pentoxide (0 < t < 28 h). Storage hardening (ΔP) of the samples was then determined by measuring the increase in Wallace plasticity (P) (macro-scale) and by analyzing their mesostructure (meso-scale) using asymmetrical flow field flow fractionation (A4F). Monitoring ΔP as a function of structuring time revealed a diversity of behaviors specific to the genotype from which the rubber originated. For example, NR samples from genotypes GT1 and PB235 exhibited different kinetics for t < 12 h, an increase in ΔP with structuring time, but reached the same final plateau (t > 12 h). An A4F analysis of the samples was used to quantify the fraction of microaggregates smaller than 1 μm (microgel<1μ). The microgel<1μ rate decreased with structuring time to varying extents depending on the genotype. A very significant negative relationship was found between ΔP and the microgel<1μ rate, indicating that the NR samples that hardened the most contained the lowest microgel<1μ rate, but the highest macrogel rate.
期刊介绍:
Polymer Testing focuses on the testing, analysis and characterization of polymer materials, including both synthetic and natural or biobased polymers. Novel testing methods and the testing of novel polymeric materials in bulk, solution and dispersion is covered. In addition, we welcome the submission of the testing of polymeric materials for a wide range of applications and industrial products as well as nanoscale characterization.
The scope includes but is not limited to the following main topics:
Novel testing methods and Chemical analysis
• mechanical, thermal, electrical, chemical, imaging, spectroscopy, scattering and rheology
Physical properties and behaviour of novel polymer systems
• nanoscale properties, morphology, transport properties
Degradation and recycling of polymeric materials when combined with novel testing or characterization methods
• degradation, biodegradation, ageing and fire retardancy
Modelling and Simulation work will be only considered when it is linked to new or previously published experimental results.