Polyamide Based Blends

Table 10.14. Drying conditions for polyamides-based blends "...

Table 10.28a. Injection molding conditions for polyamide-based blends — Part A...

Apart from cellulose, direct dyes have a strong affinity to wool and polyamide fibers. Blends of cellulose with wool ( half wool ) used to occupy a considerable segment of the market, but are today without any significance. However polyamide (PA) fibers are included in articles made of cellulose fibers to improve dimensional stability, ease of care, and durability, e.g., in sportswear and knitwear, corduroy fabrics, or plush articles, in which a PA pile is often anchored to a cellulose fabric base. Different dyeing methods are described in [50 pp. 433-4371, [6, p. 570],... 

D S International markets a family of polyamide-based engineering blends Dexpro (PA/PP) and Dexlon (PA/PP) in which the PP is male-ated, and Dexcarb (PA/PC) in which a poly-etheramide and a maleated PP or EPR are used as compatibilizer/impact modifier additives. 

Bio-based and recycled polymers often have short-lifecycles compared to oil-based virgin resins. We studied bio-based (PAX) and recycled (PA6) polyamide (PA) blends [LOU 13]. Scanning electron microscopy (Figure 12.4) shows that the formulations are composed of 75% PA6 and 25% PAX by mass (denoted PA6/PAX (25/75)) and PAX nodules appear in the PA6 matrix. To refine the morphology and improve PA6/PAX interfaces, we conducted reactive compatibilization to couple the... 

S. C. Tjong, R. K. Y. Li, and X. Xie. Properties of in situ composites based on semiflexible thermotropic liquid crystalline copolyesteramide and polyamide 66 blends. Polym. J. (Tokyo), 32 907-914,2000. 

Polyamides such as PA6 are engineering thermoplastics with high heat and solvent resistance properties and hence make ideal thermoplastic matrix candidates of choice to make high-performance TPVs with dynamically vulcanized mbber blends. Although nylon blends with low rubber content have been known for a long time as impact-modified nylons, as discussed under Sect. 19.7.1, elastomeric TPV blends of polyamide with high rubber content (>60 %) have not been commercially available until recently. Because of their higher thermal and chemical resistance performance, the polyamide-based TPVs have often been called super-TPVs (Leaversuch 2004). 

The demand for polyamide-based flexible polymer blends, particularly those free from plasticizers, seems to be increasing. Flexible polyamide blends (Saltman and Vamell 1988 Saltman 1992) containing <50 % PA-6 or PA-66 and >50 % acrylic elastomers have been commercialized by DuPont (Zytel FN) as a plasticizer-free, low-modulus composition with good low-temperature toughness, resistance to thermal-aging and solvents (particularly to fluorocarbon refrigerants) (Table 19.23). Although flexible polyamide blends contain <50 % polyamide. 

Ozkoc, G., Bayram, G., and Quaedflieg, M. (2008) Effects of microcompounding process parameters on the properties of AB8/polyamide-6 blends based nanocomposites. J. Appl. Polym. Sd., 107, 3058. 

Dencheva N, Denchev Z and Oliveira M J (2010) Microstructure studies of in situ composites based on polyethylene/polyamide 12 blends, Macromolecules 43 4715-4726. 

Dencheva N, Nunes T, Oliveira M J and Denchev Z (2005) Microfibrillar composites based on polyamide/polyethylene blends. 1. Structure investigations in oriented and isotropic polyamide 6, Polymer 46 887-901. 

Dencheva N, Denchev Z, Oliveira M J and Funari S S (2010) Microstructure studies of in situ composites based on polyethylene/polyamide 12 blends, Macromolecules 43 4715-4726. Polaskova M, Cermak R, Sedlacek T, Kalus J, Obadal M and Saha P (2010) Extrusion of polyethylene/poljTDropylene blends with microfibrillar-phase morphology, Polym Compos S1 1427-1433. Wang H, Guo J and He Y X (2011) Rheology and thermal properties of polypropylene/poly(phenyl-ene sulfide) microfibrillar composites, Adv Mater Res 194-196 1506-1509. 

Milling the surface may be necessary for a painted or dirty surface, but this can be done in a few seconds with hand held abraders. Although the reflection spectra obtained do not resemble absorption spectra, they can be transformed mathematically to give comparable results. Even without the transformation the data obtained is sufficient to set up a specific identification procedure that can recognise subtle differences in polymer structure and composition. MIR can identify and separate polymers of a similar type e.g. different form of polyamides or blends that only vary in proportion of polymers present [8]. A number of rapid identification methods are now marketed, based on MIR with sealed specular reflectance attachments. Both large scale and portable systems are available. The method can be automated and used in conjunction with a reference collection of spectra can visually display the most probable polymer type. The Bruker system P/ID 22 has been developed and tested in conjunction with the European Automobile Manufacturers Association... 

Metal complex dye based on Cu, Cr, and Ni for dyeing of wool, polyamide, and blends with manmade cellulosic fiber should only be permitted in dyeing, and provided MSDS of such dyes is supplied for verification. 

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