Arylon

The process of blending with another glassy polymer to raise the heat distortion temperature is not restricted to polycarbonate, and the polysulphones are obvious candidates because of their higher Tg. One blend has been offered (Arylon T by USS Chemicals) which has a higher softening point than the ABS-polycarbonates. 

A 50/50 blend of Udel and ABS based on a-methylstyrene was introduced by Uniroyal but is now marketed by USS Chemicals as Arylon T. This material has a heat deflection temperature almost identical to that of the unfilled Mindel materials (150°C). 

One such material is the copolymer first marketed by the Japanese company Unitika in 1974 as U-Polymer and more recently by the Belgian company Solvay as Arylef and Union Carbide as Ardel. (Around 1986 the Union Carbide interest in Ardel, as well as in polysulphones, was taken over by Amoco.) Similar polyarylates have since been marketed by Hooker (Durel), Bayer (APE) and DuPont (Arylon). This is a copolyester of terephthalic acid, isophthalic acid and bis-phenol A in the ratio 1 1 2 Figure 25.23). 

Statistical copolymerization of ethylene glycol and 1,4-butanediol with dimethyl ter-ephthalate results in products with improved crystallization and processing rates compared to poly(ethylene terephthalate). Polyarylates (trade names Ardel, Arylon, Durel), copolymers of bisphenol A with iso- and terephthalate units, combine the toughness, clarity, and proce-sibility of polycarbonate with the chemical and heat resistance of poly(ethylene terephthalate). The homopolymer containing only terephthalate units is crystalline, insoluble, sometimes infusible, and difficult to process. The more useful copolymers, containing both tere- and isophthalate units, are amorphous, clear, and easy to process. Polyarylates are used in automotive and appliance hardware and printed-circuit boards. Similar considerations in the copolymerization of iso- and terephthalates with 1,4-cyclohexanedimethanol or hexa-methylene diamine yield clear, amorphous, easy-to-process copolyesters or copolyamides,... 

A whole series of high-performance polyester LCPs was introduced in 1985. They were assembled from p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid. Polyarylates (PARs) - amorphous phenolic esters derived from aromatic dicarboxylic acids (mixtures of terephthalic acid and isophthalic acid) and biphenols such as bisphenol A - are produced by Amoco (Ardel ), Celanese (Durel ) and DuPont (Arylon ) at a volume of approx. 2000 t/a. 

There are several types of polyaryl sulfones available commercially. The classic polysulfone (Udal) was produced by the nucleophilic displacement of the chlorine substituents on bis(p-chlorophenyl) sulfone by the sodium salt of blsphenol A.Another polysulfone (Astrel) is produced by the Friedel-Crafts condensation of biphenyl with oxy-bis(benzene sulfonyl chloride). Another polysulfone (Vitrex), is produced by the alkaline condensation of bis(chlorophenyl) sulfone. (28.)Blends of polysulfones with ABS (Arylon, Mlndel) and SAN (Ucardel) are available. 

Arylon . [DuPont] Polyarylate resin high-performance thern lastic engi-nening pedymer for elecironics/eh ., mech., lighting/optical, medical applications, househoM elec, goods. 

PAr s are aromatic amorphous polyesters, viz. U-polymer , Ardel D-lOO, Durel , Arylon , etc. Their T = 188°C and HOT = 120-175°C. Blends with PPS have been developed to improve the performance of PAr — processability, rigidity and hydrolytic stability. 

These polyesters, [-0-(t)-C(CH3)2-(t)-C02-(t)-C0-]jj (Tg = 188°C, and HDT = 120-175°C), were introduced in 1974. The commercial resins include U-polymer , Ardel , Durel , and Arylon . Their advantages include transparency, good weatherability and high HDT. PAr has been blended with nearly all resins, including ABS, EPDM, lonomers, LCP, PA, PB, PBI, PBT, PC, PEI, PEK, PET, Phenoxy, PMB, PS, PPE, PPS, etc. Three types of PAr blends are of particular importance — those with polyesters, PEST, polyamides, PA, and with polyphenylenesulhde, PPS. A summary of PAr blends is provided in Table 1.76. 

In any given fire retardant one or more above methods may be used. The effect of a fire-retardant strongly depends on the basic chemical structure of the polymeric material. Owing to complexity of the processes and the experimental limitations, it is difficult to predict which mechanism is most important or operative for any system. A list of commercially available fire-retardants is given in Appendix-1. These materials are classified as organic, inorganic and reactive types. A fact to be kept in mind is that for blends or alloys, the fire retardancy behavior is usually between those of the base resins for example, consider Arylon and Kydene (acrylic/PVC) [Landrock, 1983]. 

Several companies have marketed polyarylates under the trade names U-polymer (Unitika of Japan), Arylef (Solvay of Belgium), Ardel (Union Carbide), and Arylon (Du Pont). These are noncrystallizing copolymers of mixed phthalic acids with a bisphenol and have repeat units of the type shown above. They are melt processable with Tg and heat distortion temperatures in the range of 150-200°C and have similar mechanical properties to polycarbonate and polyethersulfones (see later). 

The polymers are useful for electrical and mechanical components that require good heat resistance and for lighting fixtures and consumer goods that operate at elevated temperatures, such as microwave ovens and hair dryers. Potential uses of the somewhat cheaper arylon type polyesters include exterior car parts, such as body panels and bumpers. Typical properties of aromatic polyesters mentioned above are shown in Table 4.14. 

Property Ekonol Arylef or Ardel Arylon Vectra (Range for Various Grades)... 

See Sodium dodecylbenzenesulfonate Arylene M40, Arylene M60, Arylene M75. See Dioctyl sodium sulfosuccinate Arylide yellow FGL. See Pigment yellow 97 Arylon LP 401 NC10, Arylon LP FR-402 NC10. See Polyarylate resin... 

Ardel D-240 J[BP Amoco Polymers http //WWW. bpamocoengpolymers. com] Arylon LP401 NC10t[DuPont http //www.dupontcom, Arylon LP FR-402 NC10 t[DuPont http //www.dupont.com]... 

Fenvalerate 51706-10-6 Ardel D-100 Ardel D-170 Ardel D-240 Arylon LP401 NC10 Arylon LP FR-402 NC10 Durel 400... 

In these blends, ABS s role is to improve flowabihty and reduce cost, while that of PSF is to improve the shape retention at high temperatures. ABS/PSF blends are compatibilized either by phenoxy, EVAc-GMA, or SMA copolymers. They have good processability, high notched Izod impact strength, plateability, hydrolytic stability, and economy. However, they may show poor surface and weld-line strength. Arylon and Mindel A are examples of the commercial ABS/PSF alloys, while Ucardel is an example of PSF blends with SAN. Evolution of ABS/PSF blends technology is summarized in Table 1.19. 

SMA copolymers (Golovoy and Cheung 1994), siloxane-polyarylene polyether copolymers, or high temperature MBS. MindeF A and Arylon are examples of the commercial ASA/PSF blends. They show good processability, toughness, plateabdity, and heat and water resistance. 

The need for an expanding product line led to the development of alloys and composites based on UDEL Polysulfone. Union Carbide introduced a polymer alloy named UCARDEL designed for specific markets in 1971. At about the same time, Uniroyal Inc. introduced an ABS modified UDEL Polysulfone named Arylon T for chrome plated applications requiring higher heat resistance than ABS. 

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