Sag properties

DIN 52 454 1974 Testing of sealing compounds for sealing and glazing in building constructions non-sag properties. 

The performance expected from a sealant and the polymer used in its production determine the type of fillers used. From the point of view of performance, sealants can be divided into these having plastic behavior and these with elastomeric behavior. Sealants which have plastic behavior are low-cost and low-performance products which are being gradually eliminated from the market. These sealants use inexpensive fillers to lower cost and regulate non-sag properties. Typical fillers used in these products are calcium carbonate and some fibrous materials which are used as replacement for asbestos which was very popular in the past. This combination of fibrous and spherical particles provided a useful tool to the sealant formula-tor to regulate non-sag properties which are very important in sealants. Fibers have also been used to reinforce these products because the properties of polymers were poor. 

NS or AKS Doping [5.75, 5.76]. For the production of lamp filaments (incandescent or halide lamps), a special doping procedure is carried out which is commonly called NS or AKS doping. NS stands for the non-sag properties of the coiled lamp filament, while AKS represents the doping elements used in this process Al, K, and Si. 

Certain aspects of thermoplastic polyurethanes derived from poly(oxyethylene-oxypropylene)glycols have been described. Low temperature impact resistance and heat sag properties are dependent on segment length with 2000 molecular weight polyols being required for acceptable performance in automobile parts. 

Features Solv.-free resist, to high-temp, flow and sag Properties Tan liq. or paste dens. 8.2-8.4 Ib/gal vise. 80,000-130,000 c flash pt. (COC) > 325 R100% solids SACI 200A [Stoney Creek Tech. Sea-Land]... 

Reactive hot melts are often brittle and can exhibit poor adhesion due to their fast, quick-fixing character, which sometimes leads to poor wetting, short open-times and limited non-sagging properties. 

Non-sag properties Resistance of an adhesive to collapse or slump when extruded in bead form... 

A high performance, light-weight bonding putty with very good anti-sag properties with excellent bonding a shear strength. 

The results of the sag study provided a unique opportunity to study the changes in melt strength. Sag in blow molding is best described as the extension of the molten parison due to gravitational force. Any variance in the sag properties of a resin will have a direct effect on the shape and physical characteristics of the bottle. 

Viscosity is fairly high at low shear rates, which avoids sedimentation of pigments and provides good anti-sag properties once the paint is applied on vertical surfaces. 

Sliunp or sag properties may increase or decrease depending on the chemistry of the system. 

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