Development of slurry-jet erosion test for elastomeric materials

Abstract Fatigue crack growth can occur in elastomeric structures whenever cyclic loading is applied. In order to design robust products, sensitivity to fatigue crack growth must be investigated and minimized. The task has two basic components: (1) to define the material behavior through measurements showing how the crack growth rate depends on conditions that drive the crack, and (2) to compute the conditions experienced by the crack. Important features relevant to the analysis of structures include time-dependent aspects of rubber’s stress-strain behavior (as recently demonstrated via the dwell period effect observed by Harbour et al.), and strain induced crystallization. For the numerical representation, classical fracture mechanical concepts are reviewed and the novel material force approach is introduced. With the material force approach at hand, even dissipative effects of elastomeric materials can be investigated. These complex properties of fatigue crack behavior are illustrated in the context of tire durability simulations as an important field of application.

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Hydraulic fluid power. Compatibility between fluids and standard elastomeric materials

10.3403/02545654u ◽

2015 ◽

Keyword(s):

Fluid Power ◽

Hydraulic Fluid ◽

Elastomeric Materials

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Hydraulic fluid power. Compatibility between fluids and standard elastomeric materials

10.3403/02545654 ◽

2002 ◽

Keyword(s):

Fluid Power ◽

Hydraulic Fluid ◽

Elastomeric Materials

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Sustainable Myrcene-Based Elastomers via a Convenient Anionic Polymerization

Polymers ◽

10.3390/polym13050838 ◽

2021 ◽

Vol 13 (5) ◽

pp. 838

Author(s):

David Hermann Lamparelli ◽

Magdalena Maria Kleybolte ◽

Malte Winnacker ◽

Carmine Capacchione

Keyword(s):

Anionic Polymerization ◽

Sodium Hydride ◽

Reactivity Ratios ◽

Molecular Weights ◽

Styrene Copolymers ◽

Wide Range ◽

Elastomeric Materials ◽

Complete Study ◽

Anionic Copolymerization ◽

Trialkylaluminum Derivatives

Soluble heterocomplexes consisting of sodium hydride in combination with trialkylaluminum derivatives have been used as anionic initiating systems at 100 °C in toluene for convenient homo-, co- and ter-polymerization of myrcene with styrene and isoprene. In this way it has been possible to obtain elastomeric materials in a wide range of compositions with interesting thermal profiles and different polymeric architectures by simply modulating the alimentation feed and the (monomers)/(initiator systems) ratio. Especially, a complete study of the myrcene-styrene copolymers (PMS) was carried out, highlighting their tapered microstructures with high molecular weights (up to 159.8 KDa) and a single glass transition temperature. For PMS copolymer reactivity ratios, rmyr = 0.12 ± 0.003 and rsty = 3.18 ± 0.65 and rmyr = 0.10 ± 0.004 and rsty = 3.32 ± 0.68 were determined according to the Kelen–Tudos (KT) and extended Kelen–Tudos (exKT) methods, respectively. Finally, this study showed an easy accessible approach for the production of various elastomers by anionic copolymerization of renewable terpenes, such as myrcene, with commodities.

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Modified Nanoclays/Straw Fillers as Functional Additives of Natural Rubber Biocomposites

Polymers ◽

10.3390/polym13050799 ◽

2021 ◽

Vol 13 (5) ◽

pp. 799

Author(s):

Justyna Miedzianowska ◽

Marcin Masłowski ◽

Przemysław Rybiński ◽

Krzysztof Strzelec

Keyword(s):

Natural Rubber ◽

Raw Materials ◽

Research Work ◽

Damping Properties ◽

Main Research ◽

Functional Additives ◽

Different Types ◽

Elastomeric Materials ◽

Research Goal ◽

The Impact

Increasingly, raw materials of natural origin are used as fillers in polymer composites. Such biocomposites have satisfactory properties. To ensure above-average functional properties, modifications of biofillers with other materials are also used. The presented research work aimed to produce and characterize elastomeric materials with a straw-based filler and four different types of montmorillonite. The main research goal was to obtain improved functional parameters of vulcanizates based on natural rubber. A series of composites filled with straw and certain types of modified and unmodified nano-clays in various ratios and amounts were prepared. Then, they were subjected to a series of tests to assess the impact of the hybrids used on the final product. It has been shown that the addition of optimal amounts of biofillers can, inter alia, increase the tensile strength of the composite, improve damping properties, extend the burning time of the material and affect the course of vulcanization or cross-linking density.

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Numerical Approach for the Assessment of Micro-Textured Walls Effects on Rubber Injection Moulding

Polymers ◽

10.3390/polym13111739 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1739

Author(s):

María García-Camprubí ◽

Carmen Alfaro-Isac ◽

Belén Hernández-Gascón ◽

José Ramón Valdés ◽

Salvador Izquierdo

Keyword(s):

Surface Texturing ◽

Injection Pressure ◽

Numerical Approach ◽

High Viscosity ◽

Reduced Order ◽

Flow Perturbation ◽

Injection Process ◽

Elastomeric Materials ◽

Ring Seal ◽

Elastomeric Seals

Micro-surface texturing of elastomeric seals is a validated method to improve the friction and wear characteristics of the seals. In this study, the injection process of high-viscosity elastomeric materials in moulds with wall microprotusions is evaluated. To this end, a novel CFD methodology is developed and implemented in OpenFOAM to address rubber flow behaviour at both microscale and macroscale. The first approach allows analyzing the flow perturbation induced by a particular surface texture and generate results to calculate an equivalent wall shear stress that is introduced into the macroscale case through reduced order modelling. The methodology is applied to simulate rubber injection in textured moulds in an academic case (straight pipe) and a real case (D-ring seal mould). In both cases, it is shown that textured walls do not increase the injection pressure and therefore the manufacturing process is not adversely affected.

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Thermal and Mechanical Behavior of Elastomers Incorporated with Thermoregulating Microcapsules

Applied Sciences ◽

10.3390/app11125370 ◽

2021 ◽

Vol 11 (12) ◽

pp. 5370

Author(s):

Ana M. Borreguero ◽

Irene Izarra ◽

Ignacio Garrido ◽

Patrycja J. Trzebiatowska ◽

Janusz Datta ◽

...

Keyword(s):

Latent Heat ◽

Continuous Improvement ◽

Low Density Polyethylene ◽

Molar Ratio ◽

Low Density ◽

Minimum Particle Size ◽

Synergy Effects ◽

Elastomeric Materials ◽

The Matrix ◽

Spherical Microparticles

Polyurethane (PU) is one of the principal polymers in the global plastic market thanks to its versatility and continuous improvement. In this work, PU elastomeric materials having thermoregulating properties through the incorporation of microcapsules (mSD-(LDPE·EVA-RT27)) from low-density polyethylene and vinyl acetate containing paraffin®RT27 as PCM were produced. Elastomers were synthesized while varying the molar ratio [NCO]/[OH] between 1.05 and 1.1 and the microcapsule (MC) content from 0.0 to 20.0 wt.%. The successful synthesis of the PUs was confirmed by IR analyses. All the synthesized elastomers presented a structure formed by a net of spherical microparticles and with a minimum particle size for those with 10 wt.% MC. The density and tensile strength decreased with the MC content, probably due to worse distribution into the matrix. Elastomer E-1.05 exhibited better structural and stability properties for MC contents up to 15 wt.%, whereas E-1.1, containing 20 wt.% MC, revealed mechanical and thermal synergy effects, demonstrating good structural stability and the largest latent heat. Hence, elastomers having a large latent heat (8.7 J/g) can be produced by using a molar ratio [NCO]/[OH] of 1.1 and containing 20 wt.% mSD-(LDPE·EVA-RT27).

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