Influence of excessive filler coating on the tensile properties of LDPE–calcium carbonate composites

Osman, Maged A.; Atallah, Ayman; Suter, Ulrich W.

doi:10.1016/j.polymer.2003.12.020

Cited by 143 publications

(83 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…[27,28] The required amount (1.5 mmol) of carboxylic acid (acetic C2, butyric C4, valeric C5, capric C10, and stearic C18) was added to a suspension of 50 g VP1018 in 50 mL of toluene and the mixture was stirred for 30 min at room temperature. The slurry was centrifuged and the supernatant liquid decanted.…”

Section: Filler Surface Treatmentmentioning

confidence: 99%

Surfactant Chain Length and Tensile Properties of Calcium Carbonate‐Polyethylene Composites

Osman

Atallah

2007

Macro Chemistry & Physics

Self Cite

View full text Add to dashboard Cite

Micron‐sized CaCO3 particles free of milling additives were coated with a monolayer of aliphatic carboxylic acids of different chain length (C2, C4, C5, C10, and C18). CaCO3 was compounded with LDPE at different loading, and the tensile properties of the composites were measured and correlated to the length of the alkyl chains tethered to the particles' surface. SEM indicated that the particles are well dispersed (no agglomerates). The inclusions show little influence on the polymer crystallization, and the filler surface treatment leads to a slight decrease in polymer crystallinity that grows with increasing chain length of the fatty acid. The tensile modulus, yield stress, and maximum stress increase with increasing filler volume fraction ϕ, and the dependence is a function of the length of the alkyl chains tethered to the CaCO3 surface. It seems that the interphase thickness and properties depend on the alkyl chain length and strongly influence the modulus and stresses measured. With increasing chain length in the coated organic layer, the interfacial adhesion between the inclusions and the polymer matrix decreases, and the fibril formation increases. The tensile properties are the result of a superimposition of all these effects. The yield and ultimate strains are dominated by the interfacial slippage (increases with growing alkyl chain length) that leads to debonding at high deformations. Surface treatment of CaCO3 with valeric acid leads to the maximum possible tensile modulus, yield stress, and tensile strength combined with a relatively small loss in yield and ultimate strain.magnified image

show abstract

Section: Filler Surface Treatmentmentioning

confidence: 99%

Surfactant Chain Length and Tensile Properties of Calcium Carbonate‐Polyethylene Composites

Osman

Atallah

2007

Macro Chemistry & Physics

Self Cite

View full text Add to dashboard Cite

show abstract

“…Calcite is a calcium carbonate (CaCO 3 ) polymorph important in many fields of science and technology ranging from being a component in animal skeletons [1][2][3], applications as fillers in polymers [4] or pigments in paints, and use as a catalysts [5] or substrates in chemical engineering. For many technological applications a precise control over the particle size, morphology and specific surface area would be highly desirable.…”

Section: Introductionmentioning

confidence: 99%

Growth modification of seeded calcite using carboxylic acids: Atomistic simulations

Aschauer

Spagnoli

Bowen

et al. 2010

Journal of Colloid and Interface Science

View full text Add to dashboard Cite

a b s t r a c tMolecular dynamics simulations were used to investigate possible explanations for experimentally observed differences in the growth modification of calcite particles by two organic additives, polyacrylic acid (PAA) and polyaspartic acid (p-ASP). The more rigid backbone of p-ASP was found to inhibit the formation of stable complexes with counter-ions in solution, resulting in a higher availability of p-ASP compared to PAA for surface adsorption. Furthermore the presence of nitrogen on the p-ASP backbone yields favorable electrostatic interactions with the surface, resulting in negative adsorption energies, in an upright (brush conformation). This leads to a more rapid binding and longer residence times at calcite surfaces compared to PAA, which adsorbed in a flat (pancake) configuration with positive adsorption energies. The PAA adsorption occurring despite this positive energy difference can be attributed to the disruption of the ordered water layer seen in the simulations and hence a significant entropic contribution to the adsorption free energy. These findings help explain the stronger inhibiting effect on calcite growth observed by p-ASP compared to PAA and can be used as guidelines in the design of additives leading to even more marked growth modifying effects.

show abstract

“…By decreasing the tactoid thickness, more and more increase in aspect ratio can be generated and therefore more load can be transferred to the clay layers thus improving the mechanical performance. Another important concern is the presence of the excess of surface modification molecules on the clay surface which can badly affect the properties of the composites because of their low temperature degradation [23][24][25]. The commercially available OMMT, extensively used in many reported studies, has been observed to contain excess of such modifier molecules.…”

Section: Introduction Vmentioning

confidence: 99%

Polypropylene-Layered Silicate Nanocomposites: Filler Matrix Interactions and Mechanical Properties

Mittal

2007

Journal of Thermoplastic Composite Materials

View full text Add to dashboard Cite

Various alkyl ammonium cations were ionically exchanged with the sodium cations of montmorillonites with two different cation exchange capacities (CECs). The organo-montmorillonites were compounded with polypropylene (PP) and the effect of filler-matrix interactions on the intercalation-exfoliation behavior and the mechanical properties of the composites were investigated. With increasing the chain packing density, an increase in the d-spacing was observed and for the same cation, the d-spacing of the OMMT was higher for the higher CEC clay. Covering the surface with molecules of higher cross-sectional area led to large basal plane spacing which was helpful in achieving the partial delamination of the filler in the PP matrix even without the use of conventional compatibilizers. The modulus of PP organo-montmorillonite composites was significantly enhanced, but the other tensile properties decreased indicating the increased brittleness and lack of stronger attraction forces at interface. Augmenting the filler volume fraction also led to a significant increase in the stiffness which was compared to the theoretical predictions using the Halpin Tsai model and its modified versions.

show abstract

Influence of excessive filler coating on the tensile properties of LDPE–calcium carbonate composites

Cited by 143 publications

References 25 publications

Surfactant Chain Length and Tensile Properties of Calcium Carbonate‐Polyethylene Composites

Surfactant Chain Length and Tensile Properties of Calcium Carbonate‐Polyethylene Composites

Growth modification of seeded calcite using carboxylic acids: Atomistic simulations

Polypropylene-Layered Silicate Nanocomposites: Filler Matrix Interactions and Mechanical Properties

Contact Info

Product

Resources

About