Scorching preventing

Retard or prevent chemical reactions (such as cure). See Scorch retardants. 

The standard approach to reducing scorch (e.g. discoloration resulting from oxidation) involves addition of one or more antioxidants. Scorch retardants prevent premature decomposition of peroxides and cross-linking of polymers (pre-vulcanisation). 

Synthetic aluminosilicate materials having a structure with regularly spaced channels of molecular dimensions. Accelerators may be adsorbed on this structure and remain inactive at processing temperatures but are released at curing temperatures, thus preventing any possibility of scorching. 

Even higher shear rates in the extruder cannot prevent laminar flow in the screw flights and therefore resultant unmixed particles being carried over the shearing sections. Lengthening of the residence time in the barrel also has to be restricted to limit unacceptable temperature build-up, which would result in scorched compound. It is thus necessary to have an effective means of... 

Sterilize 150 grams of shredded wheat in a oven at 100 C for one hour. Take care to prevent scorching. At the same time, sterilize a one-gallon glass jug or 4 liter boiling flask. The latter is preferred. 

Mixed stocks should be used promptly or stored at temperatures below 18°C (65°F) to prevent scorching, and great care should be taken to exclude moisture. Typical roll temperatures for calendering recommended for VITON E-60C or related FLUOREL types are38 ... 

A water bath rather than an open flame is preferable, as the water bath prevents severity of scorching or burning of the... 

Crystex . [Akzo] Sulfur and insoluble sulfur prevents sulfur bloom on uncured rubber surfaces detackifio retards bin scorch minimizes sulfur migration. 

The vegetables are spread in a thin layer on the trays or drying frames of the drier. fhe temperature for drying should be rather low to prevent scorching the product. 

Premature cure at processing tenqperature ("scorch at 121 0 is conveniently delayed or prevented by snail amounts of various phenolic and amine free-radical inhibitors and antioxidants. When the inhibitor concentration is properly chosen, the retarding effect disappears on the curing temperature (177 0. 

Chem. Descrip. Triphenyl phosphite CAS 101-02-0 EINECS/ELINCS 202-908-4 Uses Stabilizer for styrenics, engineering thennoplastics, polyesters (to regulate vise., improve color stability), polyolefins (as catalyst adjuvant), PU (to prevent scorching during curing and improve color stability), epoxies, PVC, coatings, adhesives antioxidant for epoxies Properties APHA 50 max. clear liq. m.w. 310 sp.gr. 1.180-1.186 (25/... 

Oxidative stabilizers are added to prevent yellowing or scorching , especially in large foam blocks which develop high internal temperature during manufacture. Hindered phenols such as butylated hydroxytoluene are often used. Stabilizers are usually determined by HPLC or GC analysis, although UV absorbance measurement of a foam extract can often be used for quality control. 

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