Injection-molded glass fiber composites

Akay, M. and Barkley, D. (1985) Processing-structure-property interaction in injection molded glass-fiber-reinforced polypropylene. Composite Structures, 3, 269-293. 

Liu Wanjun, Mohanty K. Amar, Drzal T. Lawrence, et al. Injection molded glass fiber reinforced poly(trimethylene terephtalate) composites Fabrication and properties evaluation. Ind. Eng. Chem. Res. 44 no. 4 (2005) 857-862. 

Bush, S. F., Impact Strengths of injection molded long glass fiber composites. Plast. Rubber Composites Proc. Appl., 24, 139 (1995). 

Mandell 3.F., Darwish, A.Y. and McGarry F.3. (1981). Fracture testing of injection-molded glass and carbon fiber-reinforced thermoplastics. In Testing Methods and Design Allowable for Fibrous Composites, ASTM STP 734 (C.C. Chamis ed.), ASTM, Philadelphia, PA, pp. 73 90. 

To summarize the points discussed, silicone rubbers are innovative. An example of this are inserts in LSR showerheads which do not become blocked and can be produced cost-effectively in the injection-molding process as composite elements with thermoplastic nylon 6.6 30 % glass fiber. Silicone rubbers, however, are also high performance, and this is evident particularly in the many applications where they have been used for years at high temperatures, for exsample seals in irons or other domestic appliances. And not least, silicone rubbers are also efficient. An example of this molds for prototyping without which cost-effective production of individual items would not in fact be possible. 

Figure 9.5. Typical fatigue S-N curves of injection molded polyamide-66 composites reinforced with ( ) 15 and (o) 30 wt% of short glass fibers...

Long fiber-reinforced thermoplastics (LFT) are a relatively new class of fiber-reinforced materials in the field of composites. According to the fiber length, they take an intermediate position between injection molded short fiber-reinforced thermoplastics (SFT) and compression molded glass mat-reinforced thermoplastics (GMT). However, LFT show better mechanical properties and even new property combinations compared to the corresponding SFT and GMT composites (Table 1). 

In PET, nucleating agents and nucleating promoters are typically introduced into injection molded PET-glass fiber composites to accelerate their crystallization rate. PLA crystallization in the injection molding process however has not been thoroughly investigated. 

Composites. The history of phenoHc resin composites goes back to the early development of phenoHc materials, when wood flour, minerals, and colorants were combined with phenoHc resins to produce mol ding compounds. In later appHcations, resin varnishes were developed for kraft paper and textile fabrics to make decorative and industrial laminates. Although phenoHcs have been well characterized in glass-reinforced composites, new developments continue in this area, such as new systems for Hquid-injection molding (LIM) and sheet-molding compounds (SMC). More compHcated composite systems are based on aramid and graphite fibers. 

Fakirov, S. and Fakirova, C., Direct determination of the orientation of short glass fibers in an injection-molded polyethylene terephthalate) system, Polym. Composites, 6, 41 (1985). 

Fig. 6.8. Fracture toughness, K, of short glass fiber-thermoplastics injection molded composites as a function of weight fraction of fiber, fVr. (O) and (A) polyethylene terephthalate (PET) matrix ( ) and (A) polycarbonate (PC) matrix. Notches made transverse (O, ) and parallel (A, A) to the mold fill direction,...

Fig. 6.9. Normalized fracture toughness, (Kc - AKQ)/K. of short glass fiber-thermoplastics injection molded composites as a function of reinforcing effectiveness parameter, ft (O) polyetheretherketone (PEEK) matrix (K = 6.5 MPa m) (A) polytetrafluoroethylene (PTFE) matrix (K = 1.9 MPaym).

Karger-Kocsis J. and Friedrich K. (1988). Fracture behaviour of injection-molded short and long glass fiber-polyamide 6.6 composites. Composites Sci. Techno . 32, 293-325,... 

Recendy, storm doors have been constmcted of advanced thermoplastic composites. Stampable, glass-mat reinforced polypropylene sheet is used to create a high strength outer skin. These compression molded skins are welded together using a friction or ultrasonic process then injection molded with a polyurethane foam core to produce an insulated structure. New technology for window frames incorporate the pultrusion of frame channels to produce a thermoset composite channel that can be filled with fiber glass for further insulation enhancement (12,31,33,34,48,49,54—56,60—67). 

---