Epoxy-Glass Microballoon Syntactic Foams: Rheological Optimization of the Processing Window

In this paper, we discuss the chemorheology of epoxy based syntactic foams containing glass microballoons of varying density, with an aim of establishing the effect of microballoon loading on its processability. The primary objective is to determine the maximum microballoon loading that disperses uniformly in the resin without the aid of any diluent. The viscosity and dynamic mechanical properties of epoxy formulations containing varying amounts of glass microballoons were established by parallel plate rheometry. Our studies reveal that solventless processing of formulations with microballoon loading > 60% poses practical difficulties due to prohibitively high viscosities, although a packing efficiency of 74% is theoretically allowed in the case of hexagonal close packing. The presence of microballoons does not alter the curing mechanism. The mechanical properties of syntactic foams were inversely proportional to the loading and type of glass microballoons.

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Dynamic Mechanical Properties of Polypropylene Syntactic Foam with Polymer Microballoons

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.7-8.289 ◽

2007 ◽

Vol 7-8 ◽

pp. 289-294

Author(s):

Hiroyuki Mae ◽

Masaki Omiya ◽

Kikuo Kishimoto

Keyword(s):

Mechanical Properties ◽

Syntactic Foam ◽

Environmental Scanning Electron Microscopy ◽

Tensile Tests ◽

Dynamic Mechanical Properties ◽

Environmental Scanning ◽

Strain Rates ◽

Syntactic Foams ◽

Bulk Specimen ◽

Polypropylene Matrix

The main objective of this study is to measure and characterize the mechanical properties of the thermoplastic syntactic foams at the intermediate and high strain rates. The syntactic foam consists of the elastically deformable microballoons in the polypropylene matrix. The four types of syntactic foams and one polypropylene bulk specimen are prepared at same manufacturing process: 0, 20, 30, 40 and 50 volume percent of microballoons. Tensile tests are conducted at nominal strain rates ranging from 10-1 to 102 (1/sec). Elastic modulus, yield stress and rupture strain are measured and the effects of microballoons on the mechanical properties are studied. In addition, fracture surfaces are observed with ESEM (Environmental Scanning Electron Microscopy). Finally, the changes of fracture mode due to microballoons are discussed.

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Effect of Glass Microballoons Size on Compressive Strength of Syntactic Foams

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.321.7 ◽

2011 ◽

Vol 321 ◽

pp. 7-10 ◽

Cited By ~ 2

Author(s):

Zhuo Chen ◽

Zhi Xiong Huang ◽

Yan Qin ◽

Min Xian Shi ◽

Qi Lin Mei ◽

...

Keyword(s):

Mechanical Properties ◽

Particle Size ◽

Compressive Strength ◽

Size Distribution ◽

Syntactic Foam ◽

Syntactic Foams ◽

Static Compression ◽

Distribution Ranges ◽

Glass Microballoons ◽

Quasi Static Compression

In this work, syntactic foams made of microballoons having same wall thickness ratio but with different particle size was prepared. Microballoons of three size distribution ranges were selected .The property of the syntactic foams were studied by quasi-static compression test. The experimental results show the microballoons size doesn’t influent the mechanical properties of the syntactic foam significantly. The failure mode of the syntactic foams was also studied in this work.

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