Mould adhesion and fouling

Silicones are complex group of materials used as Sealants and adhesives (including Pressure-sensitive adhesives) and also find application in reducing Mould adhesion and fouling. In this article, the chemical structures underlying this range of properties are explored. 

Applications requiring low adhesion take advantage of the surface properties of the methyl groups (see Mould adhesion and fouling). They include liquid silicone rubber (LSR) used in moulding applications, silicone Release coatings to dispense organic Pressure-sensitive adhesives (PSA) and silicone PSAs. 

Surface segregation of emulsifier and stabilizer molecules used in some polymerization processes is a frequent occurrence. Common contaminants generally are lubricating oils and greases, mould release agents and various airborne materials, particularly in aerosol form (see Mould adhesion and fouling). 

Mould adhesion and fouling D E PACKHAM Relevant factors such as surface layers... 

Mould adhesion - measurement D E PACKHAM Peel, blister, etc., for low adhesion Mould adhesion and fouling D E PACKHAM Relevant factors such as surface layers... 

The TMS rheometer from Negretti is effectively a modification of the Mooney viscometer principle for use with elastomeric materials. The elastomer is introduced into a cavity containing a shearing disc by injection, and measurements of torque under fixed or variable conditions of temperature and rotor speed can be made. Effective simulation of a variety of process conditions can be made. The instrument has found particular use in the investigation of rubber-to-metal adhesion behaviour, a problem of importance to mould fouling and extrusion processing. 

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