Polymer composition with complex filler for vibroprotection pneumatic hand tools

Abstract

Purpose. The analysis revealed that the harmful influence of industrial local vibration of pneumatic hand tools impact (PHTI) causes vibration disease. This illness takes the third place in the structure of occupational diseases in Ukraine. Effective antivibration means for PHTI handles are still not developed. The purpose of this investigation is to provide a vibration-absorbing polymer composition for use as a coating or as the mastic for PHTI handles. In addition to high vibration-absorbing properties the coating should have a set of technological and operational properties: high adhesion, abrasion resistance, strength, durability, resistance to aggressive liquid media and health indicators. Methodology. For the studies vibration-absorbing polymer compositions based on epoxydian oligomers (ED) brand ED-20 and oligester cyclo-cab oligomers (OCC) brand Laprolat-803 in a ratio ED: OCC = 20:80 were used. For the compositions curing aliphatic amine mark DETA was used. To obtain the necessary technological, mechanical and damping properties of the composition dispersed mineral fillers with different surface activity - hydrophilic silica soot white brand BS-50 and a hydrophobic carbon black mark PM-234 were added. Physical and mechanical properties of polymeric materials were determined by standard methods. Researches of polymers viscoelastic properties were carried out by dynamic mechanical spectroscopy, which was implemented on a torsion pendulum - a dynamic relaxometer. The dynamic viscosity of the compositions was determined by viscometer Höppler at 20 °C and a shear stress of 200 - 1300 Pa. Results. It is shown that the effect of fillers on complex structural and rheological properties increasingly depend on the chemical nature of the filler and hydrophilicity of its parts surface. It is detected that a more intensive interaction between the filler surface and the polymer at the interface limits the molecular mobility of the polymer chains near the filler’s surface in comparison with the volume of matrix. It reduces the ability of the grommet. It was revealed that the introduction of white soot - filler with a hydrophilic surface due to formation of a solid structure of physical and chemical bonds at the interface of the composition has the greatest influence on the viscoelastic properties of the polymer matrix. It is found that the best combination of physical and mechanical properties with a complex composition characterized by filling ED-20: OCC: BS-50: PM-234 = 20:80:20:8, which simultaneously has a high vibration absorbing, tensile properties, adhesion strength, abrasivity and resistance to corrosive liquids. Originality. The regularities of the influence of the structural and rheological characteristics of epoxygidroksourethane polymeric compositions filled with disperse mineral fillers of different chemical nature on the vibration-absorbing, physical, mechanical and other performance characteristics were detected. Practical value. The detected regularities allow to control the properties purposefully and to create vibration-absorbing epoxygidroksourethane polymer composite materials with the required operational characteristics. On the basis of the researching compositions the compound comprising a complex filler was developed. It may be used for PHTI vibration isolation.