Improved compression properties of polypropylene extrusion foams by supramolecular additives

Owing to the high lightweight design potential polymer foams become increasingly important. For rigid polymer foams, requiring high dimensional stability under load, a high compression modulus is a key feature. Here, we demonstrate how supramolecular additives can be utilized to control the foam morphology and to significantly improve the compression behavior of extruded foams made of linear isotactic polypropylene. Three different 1,3,5-benzenetrisamides were selected as supramolecular additives. These additives are soluble in the polymer melt and form a supramolecular nanofiber network upon cooling, acting as nucleating sites for both, foam cells and polymer crystals. It is shown that the in situ formed nanofiber network is very effective in reducing the cell size of extruded foams. Depending on the molecular structure and the concentration of the supramolecular additives, the compression modulus of polypropylene-polymer foams can be significantly increased compared to a reference foam with talc. Unexpectedly, an improvement of 100% with a concentration of only 0.02 wt% of a supramolecular additive compared to the neat polypropylene foam featuring similar densities is achieved. This improvement cannot be correlated with the foam morphology and is most likely attributed to the presence of the supramolecular nanofiber network.

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Effects of TiB2/TiCxratios on compression properties and abrasive wear resistance of in situ 50 vol.-% (TiB2–TiCx)/Al–Cu composites

Powder Metallurgy ◽

10.1080/00325899.2017.1400221 ◽

2017 ◽

Vol 61 (1) ◽

pp. 81-87 ◽

Cited By ~ 1

Author(s):

Lei Wang ◽

Feng Qiu ◽

Delong Yang ◽

Jingyuan Liu ◽

Fang Chang ◽

...

Keyword(s):

Wear Resistance ◽

Abrasive Wear ◽

Abrasive Wear Resistance ◽

Compression Properties

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Accelerated Compression Set at Elevated Temperature in Rigid Polymer Foams

Ageing Studies and Lifetime Extension of Materials ◽

10.1007/978-1-4615-1215-8_7 ◽

2001 ◽

pp. 81-86

Author(s):

Philip C. Miller Tate ◽

Sina Talal ◽

Christopher J Page ◽

R Keith Scarrow

Keyword(s):

Elevated Temperature ◽

Polymer Foams ◽

Rigid Polymer ◽

Compression Set

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Effect of specimen size, compressibility and inertia on the response of rigid polymer foams subjected to high velocity direct impact loading

International Journal of Impact Engineering ◽

10.1016/j.ijimpeng.2016.08.006 ◽

2016 ◽

Vol 98 ◽

pp. 62-74 ◽

Cited By ~ 21

Author(s):

Behrad Koohbor ◽

Addis Kidane ◽

Wei-Yang Lu

Keyword(s):

Impact Loading ◽

High Velocity ◽

Specimen Size ◽

Polymer Foams ◽

Direct Impact ◽

Rigid Polymer

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High Performance Attapulgite/Polypyrrole Nanocomposite Reinforced Polystyrene (PS) Foam Based on Supercritical CO2 Foaming

Polymers ◽

10.3390/polym11060985 ◽

2019 ◽

Vol 11 (6) ◽

pp. 985 ◽

Cited By ~ 3

Author(s):

Yidong Liu ◽

Lingfeng Jian ◽

Tianhua Xiao ◽

Rongtao Liu ◽

Shun Yi ◽

...

Keyword(s):

Supercritical Co2 ◽

High Performance ◽

In Situ Polymerization ◽

Compression Modulus ◽

Blowing Agents ◽

Foaming Process ◽

Potential Applications ◽

Polymerization Method ◽

Low Solubility

CO2 has been regarded as one of the most promising blowing agents for polystyrene (PS) foam due to its non-flammability, low price, nontoxicity, and eco-friendliness. However, the low solubility and fast diffusivity of CO2 in PS hinder its potential applications. In this study, an attapulgite (ATP)/polypyrrole (PPy) nanocomposite was developed using the in situ polymerization method to generate the hierarchical cell texture for the PS foam based on the supercritical CO2 foaming. The results demonstrated that the nanocomposite could act as an efficient CO2 capturer enabling the random release of it during the foaming process. In contrast to the pure PS foam, the ATP/PPy nanocomposite reinforced PS foam is endowed with high cell density (up to 1.9 × 106) and similar thermal conductivity as the neat PS foam, as well as high compression modulus. Therefore, the in situ polymerized ATP/PPy nanocomposite makes supercritical CO2 foaming desired candidate to replace the widely used fluorocarbons and chlorofluorocarbons as PS blowing agents.

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Mechanical Properties of In-Situ Synthesis of Ti-Ti3Al Metal Composite Prepared by Selective Laser Melting

Metals ◽

10.3390/met9101121 ◽

2019 ◽

Vol 9 (10) ◽

pp. 1121 ◽

Cited By ~ 4

Author(s):

Li ◽

Liang ◽

Tian ◽

Yang ◽

Xie ◽

...

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Selective Laser Melting ◽

Melting Process ◽

In Situ Synthesis ◽

Metal Composite ◽

Dispersion Strengthening ◽

Laser Melting ◽

Compression Properties

Titanium composite strengthened by Ti3Al precipitations is considered to be one of the excellent materials that is widely used in engineering. In this work, we prepared a kind of Ti-Ti3Al metallic composite by in-situ synthesis technology during the SLM (selective laser melting) process, and analyzed its microstructure, wear resistance, microhardness, and compression properties. The results showed that the Ti-Ti3Al composite, prepared by in-situ synthesis technology based on SLM, had more homogeneous Ti3Al-enhanced phase dispersion strengthening structure. The grain size of the workpiece was about 1 μm, and that of the Ti3Al particle was about 200 nm. Granular Ti3Al was precipitated after the aluminum-containing workpiece formed, with a relatively uniform distribution. Regarding the mechanical properties, the hardness (539 HV) and the wear resistance were significantly improved when compared with the Cp-Ti workpiece. The compressive strength of the workpiece increased from 886.32 MPa to 1568 MPa, and the tensile strength of the workpiece increased from 531 MPa to 567 MPa after adding aluminum. In the future, the combination of in-situ synthesis technology and SLM technology can be used to flexibly adjust the properties of Ti-based materials.

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Compression Properties and Its Prediction of Wood-Based Sandwich Panels with a Novel Taiji Honeycomb Core

Forests ◽

10.3390/f11080886 ◽

2020 ◽

Vol 11 (8) ◽

pp. 886 ◽

Cited By ~ 1

Author(s):

Jingxin Hao ◽

Xinfeng Wu ◽

Gloria Oporto-Velasquez ◽

Jingxin Wang ◽

Gregory Dahle

Keyword(s):

Compression Strength ◽

Sandwich Structure ◽

Mechanical Performance ◽

Compression Modulus ◽

Honeycomb Core ◽

Compression Behavior ◽

Measurement Systems ◽

Compression Properties ◽

Entire Structure ◽

Core Thickness

The transverse compression property is one of most important aspects of the mechanical performance of a sandwich structure with a soft core. An experiment, analytical method and three digital strain measurement systems were applied to investigate the compression behavior and the failure mechanism for a wood-based sandwich structure with a novel Taiji honeycomb core. The results show that the structure of the Taiji honeycomb can improve dramatically on compression strength and modulus of composite compared to that of a traditional hexagonal one. There was no obvious deflection in the transverse direction detected by the three digital images before the buckling of the honeycomb occurred. An analytical equation between the key structure parameters and properties of the composite were applied to predict its threshold stresses and modulus. The properties of the core determine the strength of the entire structure, but the compression strength decreases slightly with an elevated core thickness, and its effect on the compression modulus can be neglected. Both the surface sheets and loading speed have little impact on the compression strength and modulus, respectively.

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In-Situ X-Ray Characterization of Fiber Structure during Melt Spinning

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892500800300302 ◽

2008 ◽

Vol 3 (3) ◽

pp. 155892500800300 ◽

Cited By ~ 6

Author(s):

Michael S. Ellison ◽

Paulo E. Lopes ◽

William T. Pennington

Keyword(s):

Melt Spinning ◽

Simultaneous Detection ◽

Polymer Melt ◽

Polymer Chains ◽

Degree Of Crystallinity ◽

Structure Evolution ◽

X Ray ◽

Spinning Process

The properties of a polymer are strongly influenced by its morphology. In the case of fibers from semi-crystalline polymers this consists of the degree of crystallinity, the spacing and alignment of the crystalline regions, and molecular orientation of the polymer chains in the amorphous regions. Information on crystallinity and orientation can be obtained from X-ray analysis. In-situ X-ray characterization of a polymer during the melt spinning process is a major source of information about the effects of material characteristics and processing conditions upon structure evolution along the spinline, and the final structure and properties of the end product. We have recently designed and installed an X-ray system capable of in-situ analysis during polymer melt spinning. To the best of our knowledge this system is unique in its capabilities for the simultaneous detection of wide angle and small angle X-ray scattering (WAXS and SAXS, respectively), its use of a conventional laboratory radiation source, its vertical mobility along the spinline, and its ability to simulate a semi-industrial environment. Setup, operation and demonstration of the capabilities of this system is presented herein as applied to the characterization of the melt spinning of isotactic poly(propylene). Crystallinity and crystalline orientation calculated from WAXS patterns, and lamellar long period calculated from SAXS patterns, were obtained during melt spinning of the polymer along the spinline.

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Preparation and Properties of Rigid Polyurethane-Imide Foams

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.150-151.1119 ◽

2010 ◽

Vol 150-151 ◽

pp. 1119-1122 ◽

Cited By ~ 1

Author(s):

Xiao Ming Sang ◽

Xing Gang Chen ◽

Shou Wu Yu ◽

Gui Xiang Hou

Keyword(s):

Body Wall ◽

Polyurethane Foams ◽

Deionized Water ◽

Compressive Property ◽

Mechanical And Thermal Properties ◽

Polymer Foams ◽

Open Type ◽

Rigid Polymer ◽

Blowing Agents ◽

Polyether Polyol

A series of rigid polyurethane foams are synthesized via the reaction of isocyanate terminated polyimide prepolymers with polyether polyol. Deionized water and n-pentane are used for blowing agents. The prepolymers and polymers are characterized by conventional methods, and physical, mechanical and thermal properties are studied. The results show that in comparison to pure polyurethane foams, these rigid polymer foams exhibit improved thermal stability as well as good compressive property. SEM of the compressed body of rigid polyurethane-imide foams show that the destructive forms are open-type tear of the film and the breakdown of the cell body wall.

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