Noryl resins properties

A limitation is, however, encountered with Noryl resins indeed, because PS is a very brittle material, their impact strength decreases when the percentage of PS is raised [37]. To circumvent this problem, rubbers are added to Noryl resins to increase the toughness [39]. Thanks to the exceptional blending properties of PPO , numerous mixed materials have been developed, for instance, with diallyl phthalates, polysulfone, acrylates, coumarone-indene, or polyvinyl chloride (PVC) [39]. It has also been shown that PPO could be blended with styrene-butadiene block copolymers, hence allowing to expand the temperature of use of the resulting materials [40]. Accordingly, the combination of various... 

NORYL resins are especially noted for their outstanding hydrolytic stability. The water absorption rate of all NORYL resins, both at room temperature and at elevated temperatures, are among the lowest of any engineering thermoplastic, which contributes to the retention of properties and dimensional stability in the presence of water, high humidity and even steam environments. In addition, NORYL resins are also virtually unaffected by most aqueous solutions, detergents, acids, and bases. 

Other thermoplastic resins can be added to produce a polymer blend in order to achieve a desirable balance of mechanical/thermal properties and cost (e.g. PPO/PS, Noryl from GE). Most blends are two phase systems, where no stress transfer to the dispersed phase is possible. PPO/PS is a special case and forms a single blend Tg between the values of the PPO (210°C) and PS (100°C) depending on the relative proportion of the two polymers (e.g. about 150°C for Noryl). 

Several approaches to compatibilizing PPE blends with commercial polyolefins (polypropylene, etc.) have been reported in the literature (Lee 1990 Kirkpatrick et al. 1989). Simultaneous compatibilization and impact modification of PPE/polypropylene blends was achieved by choosing selected types of styrene-ethylene/butylene-styrene block copolymers and PPE resin of low molecular weight (Akkapeddi and VanBuskirk 1992). A family of PPE/polypropylene alloys were commercially launched by G.E. in 2001, under the Noryl PPX trade name, and these are now sold by Sabic. Typical properties of a commercial PPE/PP blend are shown in Table 19.32. These PPE/PP blends are claimed to offer a balance of cost and performance between the TPOs and other higher-cost engineering thermoplastics such as nylons, modified PET, and PBT resins. Basically, the PPE/PP blends offer a balance of key properties stiffness, toughness, chemical, and heat resistance. 

The Noryl PPX resin portfoho presently includes unfilled and filled grades. Representative properties of unfilled PPE/PP grades appear in Table 9.12. Key features of these grades include... 

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