Shear controlled orientation

Shear Controlled Orientation in Injection Moulding (SCORIM)... 

Shear controlled orientation in injection moulding (SCORIM) is based on the progressive application of macroscopic shears at the melt-solid interface during solidification in the moulding of a polymer matrix. 

Medina, E.M.G. (1996) Alignment and management of talc platelets in polypropylene matrix by the application of shear controlled orientation injection moulding (SCORIM) technology. PhD thesis, Brunei University, UK... 

Shear controlled orientation injection molding (SCORIM) is a novel technique for establishing the alignment of polymer molecules and fiber reinforcements in molded p arts. S olid-state properties, which are highly dependent on molecnlar and additive alignment, can be improved through the use of controlled orientation. 

FIGURE 14-52 Schematic diagram of shear controlled orientation injection molding. 

Figure 2 Shear controlled orientation extrusion (SCOREX)...

Figure 6 (a) Shear controlled orientation injection moulding (SCORIM). (b) Klockner puch-puir injection moulding... 

Shear controlled orientation technology was developed to optimize plastic properties by orientation of filler particles. In this patented technology, the single feed is split into a plurality of feeds which can supply pressure to the mold cavity independent of the feed channel. Figure 7.3 shows feed arrangements. The shear is applied by a controlled movement of pistons which imposes microscopic shear. A perfect alignment of fibers can be obtained. 

Modified processing techniques have been useful for thermoplastic starch polymers. Recent work [45, 46] has examined the use of coextruded sheet processing to produce polyester / thermoplastic wheat starch / polyester multilayer films. They found that adhesion strength between the layers and stability of the interface were crucial properties in controlling the final performance properties of the films. Work by Sousa [47] has examined use of the novel shear controlled orientation injection molding (SCORIM) process to control morpholoiges and provide tensile property increases of thermoplastic starch/synthetic blends. 

SCORIM shear controlled orientation of re- SIR styrene-isoprene... 

SCORTEC shear controlled orientation tech- Center... 

Application of shear-controlled orientation in injection molding of isotactic polypropylene... 

The conventional injection molding of polypropylene is introduced in the related chapter. This chapter extends the subject of injection molding of polypropylene with the addition of shear-controlled orientation in injection molding (SCORIM), which has proved to be an excellent way of managing the morphology and hence the physical properties of polypropylene [1, 2]. 

Keywords injection molding, SCORIM, structure-propjerty relationships, shear-controlled orientation, molecular orientation, SCORIM pistons, impact strength. Young s modulus, shish-kebab morphology, y-phase, a-phase, p-phase. X-ray diffraction. 

When the PP is subjected to shear-controlled orientation injection molding (SCORIM), the molecular orientation may be enhanced, resulting in a self-reinforced molding. For example, by the SCORIM method, moldings of improved stiffness (by 75%) can be obtained [3] - see the related chapter in this book. 

Single Polymer Composites via Shear Controlled Orientation Injection Molding (SCORIM) or Oscillating Packing Injection Molding (OPIM) Techniques... 

Ogbonna C I, Kakay G, Allan P S and Bevis M J (1995) The self-reinforcement of polyolefins produced by shear controlled orientation in injection molding, J Appl Polym Sci 58 2131-2135. Mano J F, Sousa R A, Reis R L, Cunha A M and Bevis M J (2001) Viscoelastic behaviour and time-temperature correspondence of HDPE with varying levels of process-induced orientation. Polymer 42 6187-6198. 

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