Impact Strength Of Nanocomposites Research Articles

Dynamic Rheological Behavior and Mechanical Properties of PVC/O-POSS Nanocomposites

The PVC/Polyhedral oligomeric silsesquioxanes containing octyl groups (O-POSS) nanocomposites were prepared. Plastic behavior and dyanmic rheology of nanocomposites were investigated. Influences of composition on storage modulus, loss modulus and complex viscosity were discussed. The mechanical properties and morphology were determined. The results show that both plastic time and balance torque of nanocomposites all decreased when O-POSS was added. The impact strength of nanocomposites can increase 8kJ/m2 when O-POSS content is 1.5 wt%, but the T g is not decreased. The O-POSS can be used as an efficient process aid and impact aid for PVC at low content.

A new conception on the toughness of nylon 6/silica nanocomposite prepared via in situ polymerization

A novel method, in situ polymerization, was used for the preparation of nylon 6/silica nanocomposites, and the mechanical properties of the nanocomposites were examined. The results showed that the tensile strength, elongation at break, and impact strength of silica-modified nanocomposites exhibited a tendency of up and down with the silica content increasing, while those of silica-unmodified nanocomposites decreased gradually. It also exhibited that the mechanical properties of silica-modified nanocomposites have maximum values only when 5% silica particles were filled. Based on the relationship between impact strength of the nanocomposites and the matrix ligament thickness τ, a new criterion was proposed to explain the unique mechanical properties of nylon 6/silica nanocomposites. The nylon 6/silica nanocomposites can be toughened only when the matrix ligament thickness is less than τc and greater than τa, where τa is the matrix ligament thickness when silica particles begin to aggregate, and τc is the critical matrix ligament thickness when silica particles begin to toughen the nylon 6 matrix. The matrix ligament thickness, τ, is not independent, which related with the volume fraction of the inorganic component because the diameter of inorganic particles remains constant during processing. According to the observation of Electron Scanning Microscope (SEM), the process of dispersion to aggregation of silica particles in the nylon 6 matrix with increasing of the silica content was observed, and this result strongly supported our proposal. © 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 789–795, 1998

A new conception on the toughness of nylon 6/silica nanocomposite prepared viain situ polymerization

A novel method, in situ polymerization, was used for the preparation of nylon 6/silica nanocomposites, and the mechanical properties of the nanocomposites were examined. The results showed that the tensile strength, elongation at break, and impact strength of silica-modified nanocomposites exhibited a tendency of up and down with the silica content increasing, while those of silica-unmodified nanocomposites decreased gradually. It also exhibited that the mechanical properties of silica-modified nanocomposites have maximum values only when 5% silica particles were filled. Based on the relationship between impact strength of the nanocomposites and the matrix ligament thickness τ, a new criterion was proposed to explain the unique mechanical properties of nylon 6/silica nanocomposites. The nylon 6/silica nanocomposites can be toughened only when the matrix ligament thickness is less than τc and greater than τa, where τa is the matrix ligament thickness when silica particles begin to aggregate, and τc is the critical matrix ligament thickness when silica particles begin to toughen the nylon 6 matrix. The matrix ligament thickness, τ, is not independent, which related with the volume fraction of the inorganic component because the diameter of inorganic particles remains constant during processing. According to the observation of Electron Scanning Microscope (SEM), the process of dispersion to aggregation of silica particles in the nylon 6 matrix with increasing of the silica content was observed, and this result strongly supported our proposal. © 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 789–795, 1998