The presence of dicumyl peroxide (DCP) causes the changes in relative melt viscovity and the morphology of blend LLDPE/EVA. It raises torque momen amplitude of polymer blend at the balance state of melting of the polymers mixture. The results of TGA show that the durability against thermo-oxidation of polymer blend containing DCP is higher than that of without DCP. The SEM photographs also shows that DCP makes LLDPE and EVA phases dispersing into each other better than the original polymer blend.
Khi muốn thiết lập một phòng nghiên cứu và phát triển trong lĩnh vực gia công nhựa, một trong những lựa chọn đầu tiên để trang bị kèm theo cho máy đùn, máy ép phun, máy trộn đó là máy đo chỉ số chảy (melt flow indexer hay melt indexer).
Máy đo chỉ số chảy cho biết tốc độ chảy nhớt của một loại nhựa nguyên chất hay một hệ phối trộn trong điều kiện nhiệt độ, áp suất nhất định.
When the plastic melt fills the mold, it displaces the air. The displaced air must be removed quickly, or it may cause burn spot (due to the fast compression of trapped air pocket by the low-thermal-conductivity polymer melt), or it may restrict the flow of the melt into the mold cavity, resulting in incomplete filling (short-shot problem). Consider the injection-molding of a air bag housing. Notice that the part consists of a thin central region and a thick rim around it. A single gate is adopted in the original design. Most of the melt flow along the part side since...
Metals are used as biomaterials due to their excellent electrical and thermal conductivity and mechanical
properties. Since some electrons are independent in metals, they can quickly transfer an electric charge and
thermal energy. The mobile free electrons act as the binding force to hold the positive metal ions together.
This attraction is strong, as evidenced by the closely packed atomic arrangement resulting in high specific
gravity and high melting points of most metals.
Thin sections and polished sections of the mortars were prepared in an impregnation unit
under vacuum with an epoxy resin. These were polished with 15 μm Al2O3 abrasive and
the final lapping was performed with diamond pastes (15–1 μm). Thin-sections were
analysed by light polarized microscopy using a petrographic polarizing Olympus BH2
microscope equipped with an Olympus DP-10 digital camera.
Paleo et al. Nanoscale Research Letters 2011, 6:257 http://www.nanoscalereslett.com/content/6/1/257
Thermal, dielectrical and mechanical response of a and b-poly(vinilydene fluoride)/Co-MgO nanocomposites
Antonio José Paleo1*, Carlos Martínez-Boubeta2, Lluís Balcells3, Carlos Miguel Costa4, Vitor Sencadas5 and Senentxu Lanceros-Mendez5
Abstract Nanocomposites of the self-forming core-shell Co-MgO nanoparticles, which were of approximately 100 nm in diameter, and poly(vinylidene fluoride) (PVDF) polymer have been prepared.