#High vs low viscosity iso#

ISO 1133 states the dimensions of cylinder, piston, and die as well as the approved weight pieces. High-pressure capillary viscometers with electric drive In such devices, the polymer sample is exposed to medium shear stresses (from 3 kPa to 200 kPa) and medium shear rates (from 2 s -1 to 200 s -1). Such a viscometer works in the same way as a weight-driven instrument (see the above section). However, the weight is replaced by a driving motor, which realizes high shear stress values (up to 900 kPa) and medium to high shear rates (around 1,500 s -1). Capillary viscometers utilizing gas pressure Typical applications are highly viscous substances, such as polymer melts, and also PVC plastisols, greases, sealants, adhesives, and ceramic masses. These devices feature a glass or steel capillary of exact inner diameter and length. The inner diameter lies between 0.2 mm and 1 mm, while the length ranges from 30 mm to 90 mm. Gas forces the sample through the capillary at a preset pressure. This method can operate in a shear rate range up to 1,000,000 s -1. Shear stress values, however, do not exceed the medium range (a typical value would be 25 kPa). Limited flow and low exotherm when curing.The dimensions of the capillary show that this kind of apparatus is designed for medium- to low-viscosity substances: mineral oils, paper coatings, and dispersions, and for polymer solutions used to produce synthetic fibers on spinning machines. Post curing at 400☏ for 1-2 hours to optimize properties. Flowable, high viscosity system, cures in 4-6 hours at 300☏ or 2-3 hours at 350☏. One component, heat cured epoxy for bonding and sealing, as well as die attach applications. Stellar electrical insulation properties. Toughened epoxy system for bonding, sealing and specialty dam-and-fill encapsulation. Successfully tested at 1,000 hours 85☌/85% RH. Cures in 60-75 minutes at 250☏, shorter times at higher temperatures. Tensile lap shear strength 2,800-3,000 psi. Resistant to thermal cycling, mechanical vibration/shock. Single component toughened epoxy adhesive with good flow properties. Ideal for bonding similar and dissimilar substrates. Potting, encapsulation, coating, sealing, impregnation compound. Meets NASA low outgassing specifications. Low viscosity, optically clear epoxy with superior electrical insulation properties. Products such as EP21TDCHT-LO and Supreme 10HTCL have a moderately flowable viscosity, whereas Supreme 10HTND-3, Supreme 3HTND-2DM-1, and EP17HTDM-2 Black offer a non-drip paste consistency, for applications where no flow is desired.įind out more about our adhesives with different viscosities. Some examples are our products EP30LV-1, EP62-1LPSP, and Supreme 112, which have extremely low viscosities and excellent wicking capabilities, for filling tiny gaps. Master Bond epoxy compounds are available in a very wide range of viscosities from as low as 100 cps to in excess of 1,500,000 cps for various bonding, coating, sealing and potting applications. Most of the epoxy resin compounds, like the great majority of other polymer systems, fall into the Non-Newtonian category.Īn epoxy’s viscosity defines the applications (such as bonding, sealing, potting etc.) that it can be used for, as well as the means by which it can be applied. In Newtonian fluids, the viscosity doesn’t depend on the shear rate, whereas in Non-Newtonian fluids, the viscosity changes based on the shear rate. Fluids are broadly classified as: Newtonian Fluids and Non-Newtonian fluids. Viscosity may be simply defined as the resistance to flow, of a liquid. High viscosity pastes are noted for their non-drip or non-sagging properties, and are used in applications where the epoxy needs to stay in its place while applying and curing. Moderate viscosity products offer convenient dispensing, and are widely used in many bonding and sealing applications. Low viscosity systems excel in many kinds of applications, including potting, encapsulation, and impregnation. Master Bond epoxy adhesives are formulated in low, medium, and high / non-drip viscosities. Viscosity is a key criterion in the epoxy selection process, for many bonding, sealing, coating, and potting applications.