Melting point blends

Low-melting-point blends of aromatic amines (e.g., Shell Chemical Curing Agent Z or Celanese Epi-Cure 841) can be used to formulate two-component epoxies, which cure satisfactorily at temperatures below 100°C. These adhesives are often used to bond heat-sensitive... 

Fig. 10. Effect on melting point of varying composition of nylon-6,6 and nylon-6, where A represents a physical blend, and B, an equiUbrated random...

Polycarbonate—polyester blends were introduced in 1980, and have steadily increased sales to a volume of about 70,000 t. This blend, which is used on exterior parts for the automotive industry, accounting for 85% of the volume, combines the toughness and impact strength of polycarbonate with the crystallinity and inherent solvent resistance of PBT, PET, and other polyesters. Although not quite miscible, polycarbonate and PBT form a fine-grained blend, which upon analysis shows the glass-transition temperature of the polycarbonate and the melting point of the polyester. 

Fig. 3. Schematic process flow diagram for an imitation cheese product having the following formulation dry ingredients, calcium caseinate (or rennet casein), 24.5 wt % tapioca flour, 3.0 wt % salt, 2.16 wt % adipic acid, 0.6 wt % vitamins and minerals, 0.1 wt % sorbic acid (mold inhibitor), 0.5 wt % fat—color blend, soybean oil hydrogenated to a Wiley melting point of 36°C, 21.3 wt % lactylated monoglycerides, 0.05 wt % red-orange coloring, 0.01 wt...

Plasticisers are comparatively uncommon but plasticised grades are supplied by some manufacturers. Plasticisers lower the melting point and improve toughness and flexibility, particularly at low temperatures. An example of a plasticiser used commercially in Santicizer 8, a blend of o- and p-toluene ethyl sulphonamide (Figure 18.18). 

The processing of blends of an amorphous material (polystyrene) and a crystalline material with a high melting point (PPO) reflects the nature of the constituent materials. The processing is mainly by injection moulding, and the major points to be considered when processing Noryl-type materials are ... 

Recently, Nitto Denko has patented a single-layer separator made from a PE/PP blend by the dry stretch process [24], According to the patent, the separator has microporous regions of PE and PP. On heating in an oven, the impedance of the separator increases near the melting point of PE and the impedance remains high until beyond the melting point of PP. However, battery performance data have not been presented. 

Most current expl fills are blends of TNT with other ingredients, and are melt-cast loaded into bombs and warheads. Typically, several thousand pounds of the flaked blend are charged to a stirred melt kettle and heated to just above the melting point of TNT. It forms a mobile slurry when molten, and is poured mto the empty bomb or shell cases, where it solidifies. Additional ingredients such as Al may be added in the melt kettle, depending on the particular formulation being poured and the particular munition product... 

The thermal properties of block copolymers are similar to physical blends of the same polymer segments. Each distinct phase of the copolymer displays unique thermal transitions, such as a glass transition and/or a crystalline melting point. The thermal transitions of the different phases are affected by the degree of intermixing between the phases. 

The copolymerization of butadiene in trans configuration with suitable comonomers represents a second route for obtaining a wide range of strain induced crystallizable elastomers, with melting point tailorable in a wide range of temperatures. These copolymers can be used, in particular, in blends with other crystallizable rubbers (e.g. synthetic cis-l,4-polyisoprene) in order to improve their "green strength". 

The waxes consist of both cyclic and paraffin hydrocarbons. At similar melting points, the waxes have a much higher molecular weight than paraffin waxes and are less stable. Ceresine waxes have a very delicate crystalline structure, with fine needle or short plate crystals. Properly constituted blends of ceresine and paraffin waxes have a dense microcrystalline structure. 

Melting point alone cannot uniquely identify an OBC. For example, blends of high and low density polyolefins also exhibit an elevated melting point at equivalent density. Sample 3 in Fig. 17 (small circle) is a 70 30 physical blend of 0.86 and 0.94 g cm-3 ethylene-octene copolymers, and the melting point is similar to the OBCs. Physical blends of polymers of such disparate densities are not phase-continuous, however, and segregate into domains of the high and low density polymers. Figure 18 reveals differences in appearance of pressed plaques of the polymer samples... 

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