Effect of a special reinforcement on the elastic properties of micro- and nanocomposites with polymer matrix

AbstractThe paper revisits some of the well-known models in the mechanics of structurally heterogeneous media for the purpose of analysing their suitability to describe properties of nanocomposites and their mechanical behaviour. It also presents a new multi-component model for predicting the mechanical properties of micro- and nanocomposites reinforced either by whiskerising the microfibres or by bristlising the nanowires. The mathematical formulation of the model is based on using the Muskhelishvili complex potentials for each domain occupied by a separate component. As an example, the effective elastic constants are computed for fibrous composites with four different densities of whiskerisation. It is shown that the increase in the number of bristles per unit surface of the fibres gives a very strong rise to the value of Young’s modulus. However, the shear modulus, being the driving parameter for the strength estimation of the entire composition, is less sensitive to this factor.

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Modeling the Influence of Structure Morphology on the Physical and Mechanical Properties of Nanocomposites Based on a Polymer Matrix and Graphene Oxide

Mechanics of Solids ◽

10.3103/s0025654420030097 ◽

2020 ◽

Vol 55 (3) ◽

pp. 316-323

Author(s):

V. P. Matveenko ◽

M. A. Tashkinov

Keyword(s):

Mechanical Properties ◽

Graphene Oxide ◽

Polymer Matrix ◽

Physical And Mechanical Properties ◽

Structure Morphology

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Effect of Dynamic Crosslinking on Mechanical Properties of PP/EPDM Blends

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19932642 ◽

1993 ◽

Vol 58 (11) ◽

pp. 2642-2650 ◽

Cited By ~ 10

Author(s):

Zdeněk Kruliš ◽

Ivan Fortelný ◽

Josef Kovář

Keyword(s):

Mechanical Properties ◽

Impact Strength ◽

Shear Modulus ◽

High Impact ◽

Necessary Condition ◽

Step Method ◽

Melt Mixing ◽

One Step ◽

High Impact Strength ◽

Dynamic Curing

The effect of dynamic curing of PP/EPDM blends with sulfur and thiuram disulfide systems on their mechanical properties was studied. The results were interpreted using the knowledge of the formation of phase structure in the blends during their melt mixing. It was shown, that a sufficiently slow curing reaction is necessary if a high impact strength is to be obtained. Only in such case, a fine and homogeneous dispersion of elastomer can be formed, which is the necessary condition for high impact strength of the blend. Using an inhibitor of curing in the system and a one-step method of dynamic curing leads to an increase in impact strength of blends. From the comparison of shear modulus and impact strength values, it follows that, at the stiffness, the dynamically cured blends have higher impact strength than the uncured ones.

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Evolution of the viscoelastic properties of painting stratigraphies: a moisture weathering and nanoindentation approach

Heritage Science ◽

10.1186/s40494-021-00552-x ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Mathilde Tiennot ◽

Davide Iannuzzi ◽

Erma Hermens

Keyword(s):

Mechanical Properties ◽

Relative Humidity ◽

Cultural Heritage ◽

Mechanical Behaviour ◽

Viscoelastic Properties ◽

Viscoelastic Behaviour ◽

Storage And Loss Moduli ◽

Heritage Studies ◽

Paint Films ◽

The Impact

AbstractIn this investigation on the mechanical behaviour of paint films, we use a new ferrule-top nanoindentation protocol developed for cultural heritage studies to examine the impact of repeated relative humidity variations on the viscoelastic behaviour of paint films and their mechanical properties in different paint stratigraphies through the changes in their storage and loss moduli. We show that the moisture weathering impact on the micromechanics varies for each of these pigment-oil systems. Data from the nanoindentation protocol provide new insights into the evolution of the viscoelastic properties dsue to the impact of moisture weathering on paint films.

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Effect of fibre content on the mechanical properties of hemp fibre woven fabrics/polypropylene composite laminates

Polymers and Polymer Composites ◽

10.1177/09673911211023942 ◽

2021 ◽

pp. 096739112110239

Author(s):

Sheedev Antony ◽

Abel Cherouat ◽

Guillaume Montay

Keyword(s):

Mechanical Properties ◽

Polymer Matrix ◽

Composite Laminates ◽

Volume Fraction ◽

Fibre Volume Fraction ◽

Fibre Volume ◽

Woven Fabrics ◽

Fibre Content ◽

Viscoelastic Behaviour ◽

Hemp Fibre

Nowadays natural fibre composites have gained great significance as reinforcements in polymer matrix composites. Composite material based on a polymer matrix reinforced with natural fibres is extensively used in industry due to their biodegradability, recyclability, low density and high specific properties. A study has been carried out here to investigate the fibre volume fraction effect of hemp fibre woven fabrics/PolyPropylene (PP) composite laminates on the tensile properties and impact hammer impact test. Initially, composite sheets were fabricated by the thermal-compression process with desired number of fabric layers to obtain composite laminates with different fibre volume fraction. Uniaxial, shear and biaxial tensile tests were performed and mechanical properties were calculated. Impact hammer test was also carried out to estimate the frequency and damping parameters of stratified composite plates. Scanning Electron Microscope (SEM) analysis was performed to observe the matrix and fibre constituent defects. Hemp fabrics/PP composite laminates exhibits viscoelastic behaviour and as the fibre volume fraction increases, the viscoelastic behaviour decreases to elastic behaviour. Due to this, the tensile strength increases as the fibre content increases. On the other hand, the natural frequency increases and damping ratio decrease as the fibre volume fraction increases.

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Effects of the Mould Pressure and Mould Pressing Time on the Properties of Graphite/Phenolic Resin Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.706-708.95 ◽

2013 ◽

Vol 706-708 ◽

pp. 95-98

Author(s):

Mi Dan Li ◽

Dong Mei Liu ◽

Lu Lu Feng ◽

Huan Niu ◽

Yao Lu

Keyword(s):

Mechanical Properties ◽

Electrical Conductivity ◽

Flexural Strength ◽

Polymer Matrix ◽

Phenolic Resin ◽

Polymer Matrix Composites ◽

Resin Composites ◽

Matrix Composites ◽

Natural Graphite ◽

Pressing Time

Polymer matrix composites made from phenolic resin are filled with natural graphite powders. They are fabricated by compression molding technique. The density, electrical conductivity and flexural strength of composite are analyzed to determine the influences of mould pressure and mould pressing time on the physical, electrical and mechanical properties of composite. It is found that the density, electrical conductivity and flexural strength of composites increased with increasing mould pressure. Under pressure of 40 MPa for 60 min, the density, electrical conductivity and flexural strength of composites were 1.85 g/cm3, 4.35  103 S/cm and 70 MPa, respectively. The decreased gaps could be the main reason for the increasing of density, electrical conductivity and flexural strength as mould pressure increases. The results also show that the density of composites increased with increasing mould pressing time.

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Morphology and Mechanical Properties of Poly(Lactic Acid) and Propylene-Ethylene Copolymer Blends: Effect of Organoclay Types

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.737.269 ◽

2017 ◽

Vol 737 ◽

pp. 269-274

Author(s):

Sirirat Wacharawichanant ◽

Chaninthon Ounyai ◽

Ployvaree Rassamee

Keyword(s):

Mechanical Properties ◽

Lactic Acid ◽

Tensile Properties ◽

Polymer Matrix ◽

Poly Lactic Acid ◽

Dispersed Phase ◽

Copolymer Blends ◽

Morphology Analysis ◽

Ethylene Copolymer ◽

Morphology And Mechanical Properties

The effects of four types of organoclay on morphology and mechanical properties of poly(lactic acid) (PLA)/propylene-ethylene copolymer (PEC) blends were investigated. The ratio of PLA and PEC was 80/20 by weight and the organoclay content was 5 phr. The morphology analysis showed that the addition of all oganocaly types could improve the miscibility of PLA and PEC blends due to the decreased of the domain sizes of PEC dispersed phase in the polymer matrix. The tensile properties showed Young’s modulus of the PLA/PEC blends was improved after adding clay treated surface with 25-30 wt% trimethyl stearyl ammonium.

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Mechanical behaviour of powders using a medium pressure flexible boundary cubical triaxial tester

Proceedings of the Institution of Mechanical Engineers Part E Journal of Process Mechanical Engineering ◽

10.1243/095440803322328881 ◽

2003 ◽

Vol 217 (3) ◽

pp. 233-241 ◽

Cited By ~ 11

Author(s):

F Li ◽

V M Puri

Keyword(s):

Shear Modulus ◽

Mechanical Behaviour ◽

Triaxial Compression ◽

Three Dimensional ◽

Volumetric Strain ◽

Confining Pressure ◽

Alumina Powder ◽

Medium Pressure ◽

Mean Pressure ◽

Confining Pressures

A medium pressure (<21 MPa) flexible boundary cubical triaxial tester was designed to measure the true three-dimensional response of powders. In this study, compression behaviour and strength of a microcrystalline cellulose powder (Avicel® PH102), a spray-dried alumina powder (A16SG), and a fluid-bed-granulated silicon nitride based powder (KY3500) were measured. To characterize the mechanical behaviour, three types of triaxial stress paths, that is, the hydrostatic triaxial compression (HTC), the conventional triaxial compression (CTC), and the constant mean pressure triaxial compression (CMPTC) tests were performed. The HTC test measured the volumetric response of the test powders under isostatic pressure from 0 to 13.79MPa, during which the three powders underwent a maximum volumetric strain of 40.8 per cent for Avicel® PH102, 30.5 per cent for A16SG, and 33.0 per cent for KY3500. The bulk modulus values increased 6.4-fold from 57 to 367MPa for Avicel® PH102, 3.7-fold from 174 to 637 MPa for A16SG, and 8.1-fold from 74 to 597MPa for KY3500, when the isotropic stress increased from 0.69 to 13.79 MPa. The CTC and CMPTC tests measured the shear response of the three powders. From 0.035 to 3.45MPa confining pressure, the shear modulus increased 28.7-fold from 1.6 to 45.9MPa for Avicel® PH102, 35-fold from 1.7 to 60.5MPa for A16SG, and 28.5-fold from 1.5 to 42.8MPa for KY3500. In addition, the failure stresses of the three powders increased from 0.129 to 4.41 MPa for Avicel® PH102, 0.082 to 3.62 MPa for A16SG, and 0.090 to 4.66MPa for KY3500, respectively, when consolidation pressure increased from 0.035 to 3.45MPa. In addition, the shear modulus and failure stress values determined from the CTC test at 2.07, 2.76, and 3.45MPa confining pressures are consistently greater than those from the CMPTC test at the same constant mean pressures. This observation demonstrates the influence of stress paths on material properties. The CTT is a useful tool for characterizing the three-dimensional response of powders and powder mixtures.

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Effect of Silane Functionalization on Properties of Poly(Lactic Acid)/Palygorskite Nanocomposites

Inorganics ◽

10.3390/inorganics9010003 ◽

2021 ◽

Vol 9 (1) ◽

pp. 3

Author(s):

Anton Kasprzhitskii ◽

Georgy Lazorenko ◽

Alexander Kruglikov ◽

Irina Kuchkina ◽

Vadim Gorodov

Keyword(s):

Mechanical Properties ◽

Lactic Acid ◽

Polymer Matrix ◽

Covalent Bond ◽

Poly Lactic Acid ◽

Hydroxyl Groups ◽

Good Dispersion ◽

Melt Compounding

Poly(lactic acid) (PLA)/palygorskite (Paly) nanocomposites were prepared using the melt compounding technique. Paly modified by 3-aminopropyltriethoxysilane (APTES) and vinyltrimethoxysilane (VTMS) was used as nanofiller for PLA with concentrations in the 1–7 wt% range. It has been found that the functionalization allows a covalent bond between the hydroxyl groups of the Paly and the PLA matrix, evidenced by the improvement in mechanical properties. Paly modification with VTMS has better properties compared with Pale modification with APTES. This indicates a better adhesion between the Paly-VTMS and PLA matrix, and a good dispersion of the nanofiller in the polymer matrix.

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Synthesis and Characterizations of Poly(Butylene Succinate) Copolyester

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1015.381 ◽

2014 ◽

Vol 1015 ◽

pp. 381-384

Author(s):

Li Liu ◽

Li Hai Cai ◽

Dan Liu ◽

Jun Xu ◽

Bao Hua Guo

Keyword(s):

Mechanical Properties ◽

Polymer Matrix ◽

Crystallization Temperature ◽

In Situ Polymerization ◽

Nucleating Agent ◽

Single Fiber ◽

Butylene Succinate ◽

Crystallization Behaviors ◽

Polymerization Method

The poly (butylene succinate) (PBS) and 3 wt% attapulgite (ATP) reinforced PBS/ATP nanocomposites with 1,6-hexanediol were fabricated using an in situ polymerization method. The crystallization behaviors indicated that ATP had effectively acted as nucleating agent, resulting in the enhancement on the crystallization temperature. The SEM results showed a superior interfacial linkage between ATP and PBS. Also, ATP could disperse as a single fiber and embed in the polymer matrix, which resulted in the improved mechanical properties.

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