Virgin carbon fibre

Figure 1.5 a) Closed life cycle for CFRP. rCF Recycled-carbon fibre rCFRP recycled-carbon fibre reinforced polymer vCF virgin-carbon fibre and vCFRP virgin-carbon fibre reinforced polymer. Reprodnced with permission from S. Pimenta and S.X Pinho, Waste Management, 2011, 31, 378. 

Virgin carbon fibre reinforced polymer Virgin polyethylene terephthalate Wide-angle X-ray scattering Wood-plastic composite(s)... 

Virgin carbon fibre Recycled carbon fibre... 

Koo and co-workers [78] attempted to develop polyamides 11 and 12 with enhanced flame retardancy and thermal and mechanical properties by the incorporation of montmorillonite clays, silica and carbon fibre-polymer nanocomposites. Flammability properties of the nanocomposites were compared with those of the virgin polyamides, using cone calorimetry with an external heat flux of 50 kW/m. Cone calorimetry was also used in an evaluation of polyamide 6 - anion modified Mg/Al interlayer formulation [79]. The data from the cone calorimeter shows that the heat production rate (HPR) and mass loss weight of the sample with 5 wt% MgAl(H-DS) decrease considerably to 664 kW/mVs and 0.161 g/mVs from 1064 kW/mVs and 0.252 g/mVs... 

Table 2.8 Comparison of the tensile strength of virgin unreinforced and carbon fibre reinforced engineering polymers ...

Licea-Claverie and co-workers [57] studied mechanical stress-strain, impact properties and also thermal properties of PA 6,6 (including some recycled PA) with mixed glass fibre and carbon fibre reinforcements and compared these properties with those of the virgin polymers. No dependence on mechanical properties because of increasing amounts of scrap in the composites was found up to 10.4 wt%. The recycled composites generally showed lower mechanical properties when compared with the virgin composites because of a poor matrix-fibre adhesion. 

Figure 4. SEM images of recycled T800S carbon fibre (a) and virgin T800S carbon fibre...

Interfacial bonding strength of the resins with the carbon fibre. A typical ball and its force-displacement curve are shown in Fig. 4. In Table 2, interfacial shear strengths of the recycled and virgin T800S carbon fibres with the two resins are listed, measured using the micro-bond test. 

Obviously, the first measure to think about could be the substitution of recycled fibre-based boxboard for foodstuff by virgin fibre-based material. The required amount of recycled fibre-based boxboard for foodstuff equals to 700,000 t/year in Germany [7]. For the substitution of the recycled fibre-based boxboard, it is simply assumed that the required virgin fibre-based board is produced totally from mechanical spruce pulp with a process yield of 97%. This would require in total additionally about 1.68 Mio m3 wood per year. The inventory study of the carbon balance of the German forests [8] indicates an average yearly wood growth of... 

Nerin and co-workers [26] examined the applicability of SEE for the extraction of several paper and board samples of different composition, including virgin and recycled fibre. They optimised the SEE using carbon dioxide for the extraction of contaminants in 15 samples of recycled paper and board. An experimental design was used for simultaneous optimisation of the variables involved in both the extraction step and the collection of the extract. Methanol was used as modifier. Several plasticisers such as diethyl phthalate, diisobutyl phthalate, di-w-butyl phthalate, dioctyl adipate, and DEHP (from 2 to 100 pg/g of paper) were found in the recycled samples. A discriminate analysis applied to all results obtained, allowed them to classify the samples in three different groups according to the content of recycled pnlp (0, 10-30, and >80% of recycled pulp), the sample thickness (from <300 to >600 pmj, and the snrface treatment of the paper. 

---