Modified PPE

Polyphenylene oxide (PPO) or Polyphenylene ether (PPE) is an amorphous polymer with a softening temperature of about 210 °C. To improve its processability it is mostly blended with PS (modified PPE, e.g. Noryl ), which is at the cost of its heat distortion temperature. The properties are excellent the applications are mainly in fine-mechanical construction, in automotive parts, in household equipment etc. 

The good compatibility of PS and polyphenylene ether (PPE) has been used for a long time to make blends that even with a PS content in excess of 50wt% still count as modified PPE. The addition of PPE results in the increase of PS s heat resistance that can be raised to the same range as that for ABS. Result is a lower cost plastic. 

To enhanced rigidity of PO, 5-35 wt% of modified PPE was added. In this application PPE can be considered a low density filler. Similar effects can be obtained adding a small quantity of other polymers, viz. PC, POM, PPS, etc. 

Modified PPE with PA and SEES moldability and mechanical properties Kodaira et al., 1994... 

Modified PPE is mainly blended with other engineering resins — most of these were aheady discussed. The principal types of PPE blends are with styrenics, with PA, and with PEST. Owing to miscibility of PPE with PS, the compatibilization is relatively simple. However, blending PPE with either PA or PEST is more challenging, since these systems require reactive compatibilization. Development of PPE grafted with acidic functionality was motivated by this need. 

LCP dispersed in either PEST, PC, PA or modified PPE replacements for fiber reinforced plastics — recyclable blends Tomitaefa/., 1993, 1994... 

Impact-modified PPE/HIPS blends parts have been blow molded for automotive applications since the mid 1980 s. In the last few years, this processing method has gained wide acceptance, as it was expanded to produce parts for the office equipment industry using flame-retarded PPE/HIPS blends and PPE/PA blends. 

Prevex (GE Plastics, USA) Modified PPE/HIPS Resistant to acid, alkali, alcohol and oil poor resistance in gasohne... 

Expandable beads made from blends of PS and modified PPE have thermal and mechanical properties significantly better than those of EPS. They are intended for high-performance applications in the packaging industry. Maximum use temperatures vary from 105 to 120°C. The smallest bead size, ranging from 300 to 500 mm can be used to make parts with wall thickness between 1 and 2.5 mm. Typical applications include microwave-resistant drinking cups and steam-cleanable, reusable packaging. 

Commercial impact modified PPE/PA blends exhibit notched Izod impact strengths ranging from 175 to 500 J/m at room temperature. They also differ in their ductile brittle transition temperature and low temperature impact behavior. The type of nylon used (PA-6 or PA-66 or copolymer type), its end group concentrations and molecular weight, and more importantly, the nature of the rubber modifier used (compatible... 

SEES. (2) The modified PPE was blended with SBS, then dispersed in a matrix resin selected from between PEI, PA, PEST, or PS [Richards and White, 1994],... 

Impact modified PMMA Impact modified POM Impact modified PP Impact modified PPE Impact modified PPS Impact modified PS Impact modified PSF Impact modified PVC Impact modifier... 

Poly(phenylene ether or oxide) (PPE), A thermoplastic produced by catalytic polymerization of 2,6-dimethyl phenol (Fig. 1.3). For the sake of better processability, styrene copolymer-modified PPO is generally used in industrial practice. The service temperature of injection moulded and extruded parts in modified PPE is up to... 

The PPE materials are always blended or alloyed with other plastics, so they are called modified PPE... 

Noryl resins modified PPE-PS. SABIC Innovative Plastics 2006. 

Modified PPE reacted with terminal amino groups of PA + SEES TSE Vacuum devolatilization, T = 290 C Kodaira et al. 1994... 

Commercial PPE/P A blends were developed by the motivation to combine the high heat resistance characteristics of PPE with the chemical resistance characteristics of the crystalline polyamide polymers (PA-66 and PA-6). Because of the inherent incompatibility between PPE and polyamides, suitable methods of compatibilization and toughening have not been developed until recently. The technology of compatibilized, impact-modified PPE/PA blends have already been discussed under polyamide blends section (Sect. 19.7). Commercial PPE/PA blends are based primarily on the lower-cost polyamide (PA6 and PA66) and most often include a rubbery impact modifier as the third blend compraient, added for a desired level of toughness (Tables 19.25 and 19.32). 

The miscible blends of PPE and styrenic resins are often referred to as modified PPE resins. The styrenic resins can vary from crystal polystyrene to high-impact polystyrene (HIPS). 

Modified PPE resins tend to assume the best features of PPE and polystyrene [19, 20]. For example ... 

Modified PPE resins are relatively resistant to burning, and judicious compounding can increase their bum resistance by using nonbrominated, nonchlorinated flame retardants, making them ECO-label compliant. 

Modified PPE resins are especially noted for their outstanding hydroljdic stability. They have no hydrolyzable bonds. Their low water absorption rates— both at room temperature and at elevated temperatures—callow the retention of properties and dimensional stability in the presence of water, high-humidity, and even steam environments. In addition, modified PPE resins are generally unaffected by a wide variety of aqueous solutions, detergents, acids, and bases. 

Modified PPE resins will soften or dissolve in many halogenated and aromatic hydrocarbons. Laboratory data are available on the chemical resistance of plastics. However, such data should only be used as a screening tool. If a material is found to be incompatible in a short-term test, it wiU usually be found to be incompatible in a similar end-use environment. The converse, however, is not always true. Favorable results in a short-term test are no guarantee of actual performance in long-term, end-use conditions. The amount of molded-in stress found in any particular part wiU have a pronounced effect upon the relative chemical compatibility of a polymer. The acceptable chemical compatibility of a polymer in an application can be determined only by exposure or immersion of prototypes and suitably stressed samples in this type of environment under actual operating conditions [21]. 

The versatility of modified PPE resins has resulted in an extensive variety of applications which include automotive interior, exterior, and under-the-hood applications computer and business equipment electrical and electronic devices health care building and construction telecommunications appliances water handling equipment and microwavable food packaging. Noryl modified PPE resins have become the world s most successful and best-known polymer blends and alloys. 

Modified PPE structural foam grades can maintain the strength required for many structural parts. They are often used as an alternative to metal. The combination of performance properties and process features can dehver superior strength and rigidity per unit weight. Structural foam grades offer enhanced heat insulation, improved electrical and acoustical characteristics, excellent dimensional stability—including low creep and water absorption, less tendency to observe sink marks on the... 

In the molding process, preexpanded heads are introduced into a closed mold and then heated, whereupon the heads soften, reexpand to fill the interstitial volume, and tjrpically fuse together without the need for external pressure. Expanded foam modified PPE materials exhibit... 

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