Reinforced reaction injection molding RRIM

Reimer-Tiemann reaction, 6 236 of salicylic acid, 22 5 Reinforced composites flax fiber in, 22 594 silylating agents and, 22 701-703 Reinforced plastics, 26 750-751 asbestos applications, 3 311 Reinforced polyester composites, 20 114 Reinforced reaction injection molding (RRIM), 25 456 Reinforcement... 

A3 + C3) Chopped fiber Reinforced reaction Injection molding, RRIM No Yes... 

The formulations given below (in parts by weight) are three examples of typical formulations from the many available, which have been designed to meet specific requirements. Noteworthy points reading the formulations are explained. An example of formulation for reaction injection molding (RIM) and reinforced reaction injection molding (RRIM) is also given,... 

Polyurethanes (PU or PUR) and polyureas are classified as TS resins, but their chemistry is so flexible that they can be formulated different ways. There are moldable solid and expanded TSs, with (RPUR) or without reinforcement, flexible and rigid foams, elastomers and thermoplastic molding compounds. As RPs they are important in reinforced reaction injection molding (RRIM) (Chapter 5) and are also available as reinforced thermoplastic molding compounds. A variant on the process employs a structural preform of the reinforcement that is placed in the mold cavity and is called structural reaction injection molding (SRIM). 

There is no single method for treating polymethane (PUR) waste, due to the different quantities, qualities, mixes, and cleanliness. It is estimated that some 125,000 t of RIM polyurethane is used worldwide, 85% in automotive parts, mainly in bumper fascias. Current technologies for physical recycling of PURs are mainly directed towards flexible and rigid foams, but systems have also been developed for recycling reinforced reaction injection molded (RRIM) PURs, on the... 

Details on reinforced reaction injection molding (RRIM) using TS polyurethane (PUR). Two-component PUR mixtures, in which a polyol and isocyanate are brought together and a fast reaction takes place to produce a solid compound with useful properties lend themselves well to molding with reinforcement. This can be a flat or preformed mat placed in the mold, or a chopped reinforcement introduced into the stream of components in the mixing head. 

Two or more liquids are mixed in a resin pot and fed at low pressure into a closed mold, where they react. This technique can be used to feed catalyzed resin into a pultrusion die. The process can be adapted to reinforced reaction injection molding (RRIM) by introducing milled or chopped fiber. 

For RPs, electroformed molds are mainly useful for autoclave molding and for closed matched die molding (cold press, low-pressure hot press, resin injection, resin transfer, low-pressure phenolic molding, and resin casting) as well as for reinforced reaction injection molding (RRIM). Prototyping can also use this technique for mold-making. 

The principal material used for RIM is polyurethane, however nylon, polyethylene, epoxy, and polyester can also be used. Chopped glass fibers and inorganic fillers have been added to these materials to increase strength and stiffness. The process then becomes known as reinforced reaction injection molding (RRIM). 

A variation of RIM is reinforced reaction injection molding (RRIM). RRIM refers to a molding process in which the resin is pumped into a closed mold that has been preloaded with dry reinforcements. Polyester resins are often used, but polyurethanes, vinyl esters, and epoxies can be molded via RIM. The advantages of RIM over other reinforced plastic molding processes are ... 

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