Properties of photocured epoxy resin materials for application in piezoelectric ultrasonic transducer matching layers.
This paper describes the acoustic properties of a range of epoxy resins prepared by photocuring that are suitable for application in piezoelectric ultrasonic transducer matching layers. Materials, based on blends of diglycidyl ether of Bisphenol A and 1,4-cyclohexanedimethanol diglycidyl ether, are described. Furthermore, in order to vary the elastic character of the base resin, samples containing polymer microspheres or barium sulfate particles are also described. The acoustic properties of the materials are determined by a liquid coupled through transmission methodology, capable of determining the velocity and attenuation of longitudinal and shear waves propagating in an isotropic layer. Measured acoustic properties are reported which demonstrate materials with specific acoustic impedance varying in the range 0.88-6.25 MRayls. In the samples comprising blends of resin types, a linear variation in the acoustic velocities and density was observed. In the barium sulfate filled samples, acoustic impedance showed an approximately linear variation with composition, reflecting the dominance of the density variation. While such variations can be predicted by simple mixing laws, relaxation and scattering effects influence the attenuation in both the blended and filled resins. These phenomena are discussed with reference to dynamic mechanical thermal analysis and differential scanning calorimetry of the samples.
Department of Pure and Applied Chemistry, University of Strathclyde, Thomas Graham Building, 295 Cathedral Street, Glasgow G1 1XL, Scotland.
Alexandre
A
Trogé
Richard L
RL
O'Leary
Gordon
G
Hayward
Richard A
RA
Pethrick
Anthony J
AJ
Mullholland
D001559:Benzhydryl Compounds; D002152:Calorimetry, Differential Scanning; D003510:Cyclohexanes / Q000737:chemistry; D004853:Epoxy Resins / Q000737:chemistry*; D004867:Equipment Design; D004987:Ethers / Q000737:chemistry; D008422:Materials Testing; D008962:Models, Theoretical; D010636:Phenols / Q000737:chemistry; D010777:Photochemistry; D013816:Thermodynamics; D014159:Transducers; D014465:Ultrasonics / Q000295:instrumentation* / Q000379:methods*; D000098826:Bisphenol A Compounds
D001559:Benzhydryl Compounds; D003510:Cyclohexanes; D004853:Epoxy Resins; D004987:Ethers; D010636:Phenols; C023353:1,4-cyclohexanedimethanol; C006780:bisphenol A; D000098826:Bisphenol A Compounds