scholarly journals The effect of foaming agent on mechanical and physical properties of Polypropylene

2018 ◽  
Vol 2 (1) ◽  
Author(s):  
SEDEF CAKIR 1 ◽  
MUHAMMED AYCICEK 1 ◽  
EDIZ ALTUN 2 ◽  
Akin Akinci 1
Keyword(s):  
Mechanical Properties ◽  
Cell Density ◽  
Cell Morphology ◽  
Injection Pressure ◽  
Skin Layer ◽  
Polymer Materials ◽  
Cell Diameter ◽  
Melt Temperature ◽  
Foaming Agent ◽  
Foaming Agents

In this study, Polypropylene (PP) foam materials were used with injection parameters such as melting, molding and injection temperatures. To produce foam materials, chemical foaming agents were used, and added to polymer materials as 1wt.%, 1.5wt.%, 2wt.%, 2.5wt.%, 3wt.%. The mechanical properties of foam samples were determined based on the parameters. Cell morphology characterization such as cell diameter, cell count, skin layer thickness and cell density, and mechanical properties such as tensile and impact strength of polymer foams were examined.Generally, the closed-cell foam structure was obtained. The most important parameters affecting the cell morphology have been injection pressure, melt temperature and amount of foaming agent. With increasing the amount of foaming agent, cell density increased, foam density and mechanical properties decreased.

Migration of Nanoclay in PP/PS Blend and Effect of Its Localization on Cell Structure

2008 ◽  
Author(s):  
Jun-Feng Zhao ◽  
Han-Xiong Huang
Keyword(s):  
Shear Flow ◽  
Cell Density ◽  
Cell Structure ◽  
Cell Diameter ◽  
Foaming Agent ◽  
Nucleation Sites ◽  
The Mean ◽  
Nanoclay Content ◽  
Blend Nanocomposites ◽  
Low Shear

In this work, the migration of clay in polypropylene/polystyrene (PP/PS) blend and the effect of its final localization on cell structure of microcellular foamed blend nanocomposites were studied. To observe the clay migration, a multilayered blend, alternatively superposed PS and PP/clay films with a thickness of 0.2 mm, was subjected to low shear flow. Batch foaming was performed on obtained blend nanocomposites to study the influence of the nanoclay localization on cell structure by using CO2 as the foaming agent. When subjected to flow, most clay dispersed in PP phase migrated into PS gradually. The migration of nanoclay caused smaller mean cell diameter and higher cell density to foamed PS. With the reduction of nanoclay content in PP phase, the cell density of PP foam decreased due to the reduction of heterogeneous nucleation sites and the mean cell diameter became smaller.

Advances in Microcellular Foam Processing of PLA

2016 ◽  
Vol 717 ◽  
pp. 68-72 ◽  
Author(s):  
Zhi Zhong Han ◽  
You Cheng Zhang ◽  
Wei Min Yang ◽  
Peng Cheng Xie
Keyword(s):  
Mechanical Properties ◽  
Cell Density ◽  
Cell Morphology ◽  
Expansion Ratio ◽  
Chain Extender ◽  
Microcellular Foam ◽  
Foaming Process ◽  
Microcellular Foaming ◽  
Alternative Materials ◽  
A Chain

PLA is a bio-based biodegradable plastic, which has excellent biocompatibility and biodegradability. Because the mechanical properties of microcellular foaming material is similar to petroleum-based plastics (PS), PLA foams have been considered as ideal alternative materials. However, PLA has several inherent drawbacks such as low melt strength and slow crystallization kinetics, which severely inhibit the PLA foaming process to produce high-density forms and uniform cell morphology. By adding a chain extender or nanoparticles, and blending with other biological materials, these ways could effectively enhance the expansion ratio and the cell density of PLA and improve the mechanical properties of PLA foams. The most current investigations on microcellular foaming of PLA were reviewed in the article, and outlook of PLA foams was raised.

The Influence of Technological Conditions on Cell Density and Cell Morphology of PPESK Microporous Material

2013 ◽  
Vol 423-426 ◽  
pp. 507-510
Author(s):  
Min Jie Qu ◽  
Tian Qi Li ◽  
Lai Jiu Zheng ◽  
Shi Yang Zhu ◽  
Ling Ling He ◽  
...  
Keyword(s):  
High Temperature ◽  
Cell Density ◽  
Cell Morphology ◽  
Saturation Pressure ◽  
Microporous Material ◽  
Foaming Agent ◽  
Temperature Resistance ◽  
Engineering Plastic ◽  
High Temperature Resistance ◽  
Foaming Temperature

Phthalazinone structure contained phthalaazione ether sulfone ketone (PPESK) is a kind of excellent engineering plastic with high temperature resistance and resolvability. In this paper, SC-CO2was used as foaming agent to prepare PPESK foams by temperature rising method. The influence of technological conditions like foaming time, foaming temperature and saturation pressure on cell density and cell morphology was discussed and analyzed.

Effect of Process Parameters on Mechanical Properties of Carbon Fiber Reinforced ABS Composites

2019 ◽  
Vol 815 ◽  
pp. 145-150
Author(s):  
Yu Xin Dong ◽  
Quan Wang ◽  
Chong Ying Yang ◽  
Wen Zhe Xu ◽  
Shuo Zhou ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Fiber ◽  
Tensile Stress ◽  
Process Parameters ◽  
Injection Pressure ◽  
Mold Temperature ◽  
Carbon Fiber Composites ◽  
Melt Temperature ◽  
Twin Screw ◽  
Power Content

In this paper, the carbon fiber and ABS composites were prepared in different carbon fiber power mass percent by the twin screw extruder. The mechanical properties of the ABS/CF composites were studied in different process parameters by injection molding. The influence of mold temperature, melt temperature, packing pressure and injection pressure on the mechanical properties was analyzed in different carbon fiber composites. The results show that with the content of carbon fiber increase, the tensile stress of the composite materials also increase. The effect of different carbon fiber power content on tensile stress is greater compared with process parameters.

Effects of Gate Locations on the Tensile Strength of Injection Molded Weld Lines

2013 ◽  
Vol 561 ◽  
pp. 64-69
Author(s):  
Yu Mei Ding ◽  
Xiao Hua Wang ◽  
Peng Cheng Xie ◽  
You Chen Zhang ◽  
Wei Min Yang
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Mechanical Test ◽  
Injection Pressure ◽  
Melt Temperature ◽  
Injection Speed ◽  
Appearance Quality ◽  
Study Results ◽  
Molded Parts ◽  
Injection Molded

As unfavorable molding defect, weld lines often result in reduced mechanical properties and poor appearance quality of injection molded parts. In this present work, effects of gate locations on the tensile strength of weld lines were investigated by changing the distances between two gates in 10mm, 20mm and 25mm, respectively. Test specimens were prepared with an all-electrical injection molding machine under different process parameters (injection speed, injection pressure and melt temperature). Visualization method and scanning electron microscope (SEM) were employed to further discuss mechanical test results. Study results indicated that tensile strength of injection molded weld lines was lessened as the increase of gate distances. Higher injection speed, higher injection pressure and lower melt temperature induced to lower weldline tensile strength whatever the gate locations were. Study results also illustrated that it was gate location rather than molding conditions had the most decisive influence on the weldline mechanical properties.

scholarly journals Mechanical Properties of Polypropylene (PP) – Montmorillonite (MMT) Nanocomposites for Pre-Fabricated Vertical Drain (PVD) Application

2018 ◽  
Vol 7 (4.35) ◽  
pp. 689
Author(s):  
N.A. Selamat ◽  
M.N. M.Ansari ◽  
Zainudin Yahya ◽  
Ragunatha E.Naicker
Keyword(s):  
Mechanical Properties ◽  
Impact Strength ◽  
Tensile Modulus ◽  
Injection Pressure ◽  
Optimum Process ◽  
Melt Mixing ◽  
Melt Temperature ◽  
Injection Speed ◽  
Molding Method ◽  
Vertical Drain

Polypropylene (PP) – montmorillonite (MMT) blends were prepared by melt-mixing method followed by injection molding method. The optimum process melt-temperature was set at 1950C, the injection speed of 15cc/s, injection pressure of 30MPa and cooling time of 20 sec. was used for the sample preparation. Investigation shows, addition of MMT nanoparticles have improved the mechanical properties. The tensile test and impact test were conducted at room temperature and atmospheric pressure. The tensile modulus and yield strength improved with increasing MMT content, however, elongation at break was reduced as the MMT content was increased from 2wt% to 8wt%. The Izod impact strength is also affected by the addition of MMT content. Nanocomposites based on PP containing 8wt% of MMT showed higher impact strength than the other compositions and Neat PP (control). The influence of MMT content on impact strength increased with MMT content which is a significant result required for pre-fabricated vertical drain (PVD). Further investigations are required to study the mechanical properties of the PVD using PP – MMT nanocomposites to replace the existing material (PP).

scholarly journals Effects of Polyhedral Oligomeric Silsesquioxane (POSS) on Thermal and Mechanical Properties of Polysiloxane Foam

Materials ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 4570
Author(s):  
Chunling Zhang ◽  
Jinrui Zhang ◽  
Tianlu Xu ◽  
Haofei Sima ◽  
Jiazi Hou
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Cell Density ◽  
Polyhedral Oligomeric Silsesquioxane ◽  
Cross Linking ◽  
Cell Diameter ◽  
Thermal And Mechanical Properties ◽  
Average Cell ◽  
Composite Foam ◽  
Oligomeric Silsesquioxane

The thermal and mechanical properties of polysiloxane foam are greatly improved by the addition of acrylolsobutyl polyhedral oligomeric silsesquioxane (MA0701, hereinafter referred to as MAPOSS), which has double bonds. The morphologies and properties of the polysiloxane composite foam were characterized. The average cell diameter of the composite foams decreased, while the cell density increased with increasing MAPOSS. Meanwhile, MAPOSS can enhance thermal conductivity and thermal stability. Thermal conductivity increased by 25%, and the temperature at the maximum weight loss rate increased from 556 °C to 599 °C. In addition, MAPOSS also promoted heterogeneous nucleation by functioning as a nucleating agent, which can increase cell density to improve the mechanical properties. The compressive strength of the composite foam increased by 170% compared with that of pure foam. In the composite, MAPOSS increased the cross-linking density by acting as a physical cross-linking point and limited the movement of the segments.

scholarly journals Determination of the Influence of Hydraulic Additives on the Foaming Process and Stability of the Produced Geopolymer Foams

Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 5090
Author(s):  
Michał Łach ◽  
Kinga Pławecka ◽  
Agnieszka Bąk ◽  
Katarzyna Lichocka ◽  
Kinga Korniejenko ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Portland Cement ◽  
Polyurethane Foams ◽  
Expanded Polystyrene ◽  
Foaming Agent ◽  
Foaming Agents ◽  
Foaming Process ◽  
Al Powder ◽  
The Stability

The research described in this article was aimed at determining the influence of hydraulic additives on the foaming process and the stability of the produced geopolymer foams. These foams can be used as insulation materials to replace the currently commonly used insulations such as expanded polystyrene or polyurethane foams. Geopolymers have low thermal conductivity, excellent fire- and heat-resistant properties, and have fairly good mechanical properties. Research on foamed materials shows that they have the highest class of fire resistance; therefore, they are most often used as insulation products in construction. Geopolymer foams were made of aluminosilicate materials (fly ash) and foaming agents (H2O2 and Al powder), and the stabilizers were gypsum and portland cement. Additionally, surfactants were also used. It was found that better foaming effects were obtained for H2O2—it is a better foaming agent for geopolymers than Al powder. When using a hydraulic additive—a stabilizer in the form of cement—lower densities and better insulation parameters were obtained than when using gypsum. Portland cement is a better stabilizer than gypsum (calcium sulfates), although the effect may change due to the addition of surfactants, for example.

Effect of Foaming Agent on Microcellular Unsaturated Polyester

2012 ◽  
Vol 271-272 ◽  
pp. 172-176
Author(s):  
Xue Ni Zhao ◽  
Jian Peng He ◽  
Pei Pei Zhai ◽  
Wei Ren
Keyword(s):  
Cell Size ◽  
Cell Density ◽  
Compression Strength ◽  
Unsaturated Polyester ◽  
Weight Ratio ◽  
Average Cell Size ◽  
Average Cell ◽  
Foaming Agent ◽  
Foaming Agents ◽  
Increasing Temperature

Microcellular unsaturated polyester was prepared by different foaming agents was studied. Compared with the cell size and density of microcellular unsaturated polyester prepared using azodicarbonamide (AC), the ones of microcellular unsaturated polyester prepared using NaHCO3 were small. For NaHCO3, the cell density of microcellular unsaturated polyester decreased with the increasing temperature. For microcellular unsaturated polyester prepared using NaHCO3 at 100 °C, the average cell size was about 18 μm and the cell density was 1.1×1010 cells/cm3. The compression strength at 100 °C is strongest among that of the materials at the other temperature. The average compression strength was 24.2 MPa. The compression strength-to-weight ratio of microcellular unsaturated polyester prepared at 90 °C and 100 °Cwas about twice that of unsaturated polyester.

Sign in / Sign up

Export Citation Format

Share Document