Green composite process

As the mesophase has a much lower volatile content than the original binder pitch, and because the mesophase is still deformable by molding, a carbonization process was developed by Bruckmann (19) in which mechanical pressure is applied after the green composite has been pyrolyzed at 450°C for 5 h. A tensile strength of about 800 MPa and a Young s modulus of about 150 GPa were achieved without subsequent impregnation processes. These values were measured after final baking to 950°C. 

For making CA-based green composites by process II, a two-step extrusion was used to make CA-hemp biocomposite pellets which were then injection molded. The first step was to produce CA plastic granules from CA powder and 30 wt.% TEC plasticizer. [Note CA needs an external plasticizer added to enhance its flow and allow processing below its degradation temperature (230°C), which is near... 

LCA methodology applied in the development of new polymer composites is a relative new field, but it has already been widely used in many industrial sectors as a very useful tool to drive the choice of materials and processes towards a more sustainable production system. Several LCA applications to both traditional composites and new green composites have pointed out that the benefits of using green composites produced with natural fibres and bio-derived matrices, compared to traditional composites, appear superior, and their market opportunities are increasing for many industrial sectors. 

The compositions, processability and properties of elastomers prepared using the one-shot process are given in Tables 9.10 to 9.12. For the 4000-MW, EO-capped diol, the upper hardness processability limit via hand casting is about 85 Shore A as indicated by the green strength in Table 9.10. Machine casting using a shorter pot life (30 to 45... 

Figure 14.19 The bulk density of carbon-carbon composites after successive process cycles with Torayca M40B and pitch The decrease of density after the first cycle necessitates further processing. GC = green composite 1C = first carbonization cycle 1IR, 2IR, SIR and 4IR = successive impregnation and recarbonization cycles. Source Reprinted with permission from Rhee B, Ryu S, Fitzer E, Fritz W, High Temp-High Pressures, 19(6), 677-686, 1987. Copyright 1987, Pion Ltd.

Bhaduii SK, Sen SK, Dasgupta PC (1983) Structural studies of an acidic polysaccharide isolated from the leaf fibre of pineapple (Ananas comosus MERR). Carbohydr Res 121 211-220 Bhattacharya TB, Biswas AK, Chatterjee J, Pramnick D (1986) Short pineapple leaf fibre reinforced rubber composites. Plast Rubb Process Appl 6 119-125 Bismarck A, Mishra S, Lampke T (2005) Plant fibers as reinforcement for green composites. In Mohanty AK, Misra M, Drzal LT (eds) Natural fibers, biopolymers and biocomposites. Taylor Francis, EL, Boca Raton... 

Several of these modified SPI and SPC resins were used to fabricate fiber, yam and fabric reinforced green composites. The fabrication process and properties of these composites are discussed in the next section. Data for green composites using nanoclay were, however, not available at this time. 

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