Polyester-polyamide blends

Polymer Blends.—In addition to the work on polyester—polyamide blends reported in Section 2, several other papers describe the characteristics of various polymer formulations with polyamides. Biconstituent fibres have been formed from nylon-6 and poly(ethylene terephthalate). The same polyamide and nylon-12 have been blended with acrylonitrile-butadiene-styrene copolymer and the temperature and the concentration dependence of the dynamic modulus evaluated. The rheological properties of acrylonitrile-styrene copolymer/nylon-6 mixture have also been reported. Fourier transform infrared studies of nylon-6 and PVC have indicated the presence of specific interactions between the two polymers in both the molten and solid states. Finally X-r y studies carried out on injection-moulded blends of nylon-6, -12, and -66, have revealed that the addition of small amounts of the second component initiates formation of the y-crystalline phase within the nylon-6 polymer matrix. ... 

Essentially nonionic soil-release agents comprise polyesters, polyamides, polyurethanes, polyepoxides and polyacetals. These have been used mainly on polyester and polyester/ cellulosic fabrics, either crosslinked to effect insolubilisation (if necessary) or by surface adsorption at relatively low temperature. Polyester soil-release finishes have been most important, particularly for polyester fibres and their blends with cellulosic fibres. These finishes, however, have much lower relative molecular mass (1000 to 100 000) than polyester fibres and hence contain a greater proportion of hydrophilic hydroxy groups. They have been particularly useful for application in laundering processes. These essentially nonionic polymers may be given anionic character by copolymerising with, for example, the carboxylated polymers mentioned earlier these hybrid types are generally applied with durable press finishes. 

Mixed esters, such as isopropylphenyl diphenyl phosphate and tcrt-butylphenyl diphenyl phosphate, are also widely used as both plasticizers/flame retardants for engineering thermoplastics and hydraulic fluids.11 These esters generally show slightly less flame-retardant efficacy, when compared to triaryl counterparts however, they have the added advantage of lower smoke production when burned. Some novel oligomeric phosphate flame retardants (based on tetraphenyl resorcinol diphosphate) are also employed to flame retard polyphenylene oxide blends, thermoplastic polyesters, polyamides, vinyls, and polycarbonates. 

REMOL ASN liquid has an excellent dispersing and compatibil-izing action in one-bath dyeing of wool or polyamide blends with acrylic fibers using anionic and cationic dyes and in dyeing polyester/acrylic fibers with disperse and cationic dyes. 

These parameters have been found useful to predict miscibility of blends containing one component whose structure systematically varied, e.g., polyesters with either halogenated polymers or Phenoxy [Prud homme, 1982 Harris et al, 1983 Woo ei al, 1985 Woo et al, 1986], polyamide blends [Ellis, 1989], ternary blends [Shah et al, 1986] and other systems, viz. SAN/ PMMA, SAN/PC, polyethyloxazoline/polyester, PPE with a mixture of P(oClS) and P(pClS), PC/PCL/Phenoxy, and many more. 

A general review of Interchange Reactions Involving Condensation Polymers describes early work on redistribution reactions in the melt blends of polyesters, polyamides, and polyester + polyamide [Kotliar, 1981],... 

In comparing the different blends, the specific advantages of each type, as well as any potential overlap in performance with other type of blends have also been discussed. The fundamental advantage of polymer blends viz. their ability to combine cost-effectively the unique features of individual resins, is particularly illustrated in the discussion of crystalline/amorphous polymer blends, such as the polyamide and the polyester blends. Key to the success of many commercial blends, however, is in the selection of intrinsically complementing systems or in the development of effective compatibilization method. The use of reactive compatibilization techniques in commercial polymer blends has also been illustrated under the appropriate sections such as the polyamide blends. 

Blends of condensation polymers containing functional groups internally or at chain ends (such as polycarbonates, polyesters, polyamides, and the like) may undergo intermolecular exchange reactions when mixed in the molten... 

Uses Flame retardant, plasticizer for engineering thermoplastics incl. PPO blends, thermoplastic polyesters, polyamides, vinyls, and polycarbonates... 

The compatibUization technique has been used successfully in preparing EPDM/ polyamide and polyester blends, silicone rubber and polyamide blends, and blends of two dissimilar TPVs [25, 28-30]. 

Examples of Applications of Reactive Blending in Polyester and Polyamide Blends... 

This section presents and discusses a few examples of reactive blending during the preparation of polyester and polyamide blends, by reaction of epoxy/carboxylic acid (polyesters blends) and anhydride/amine (polyamide blends) groups. 

Tetraphenyl Resorcinol Diphosphate [57583-54-7], This is the main component of an oligomeric phosphate flame retardant, Akzo Nobel s FYROLFLEX RDP or Great Lakes Chemical s REOFOS RDP, designed for use in engineering thermoplastics such as polyphenylene oxide blends (105,106), thermoplastic polyesters, polyamides, polycarbonates, and ABS-polycarbonate blends. A major use was in PPO-HIPS blends and later in ABS-polycarbonate blends (107). It is a colorless to light-yellow liquid, viscosity 400-800 mPa s at 25°C, and a pour point of - 12°C. It is less volatile than the triaryl phosphates and has a higher percentage of phosphorus (11% P) than triphenyl phosphate. 

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