Polyphenylene ether-polystyrene blends

R. S. Clough and M. A. Perez. Melt blending polyphenylene ether, polystyrene and curable epoxy. US Patent 6518 362, assigned to 3M Innovative Properties Company (Saint Paul, MN), February 11, 2003. 

Xylenol 2,6-Xylenol polysiloxane resin improver Benzene phosphinic acid polystyrene derivative mfg, crosslinked Styrene/DVB copolymer polystyrene/polyamide/PC blends Polyphenylene ether polystyrenes Solvent yellow 33... 

Polymer Blends. Blending of polymers with each other accounts for approximately 40 percent of the present plastics market, and the practice is growing continually, because it permits the development of improved properties without the cost of inventing new polymers. When polymers are fairly miscible, as in the polyethylenes, and in polyphenylene ether plus polystyrene, blending can be used to produce intermediate properties and balance of properties. Most polymer blends... 

Polystyrene is one of the most widely used thermoplastic materials ranking behind polyolefins and PVC. Owing to their special property profile, styrene polymers are placed between commodity and speciality polymers. Since its commercial introduction in the 1930s until the present day, polystyrene has been subjected to numerous improvements. The main development directions were aimed at copolymerization of styrene with polar comonomers such as acrylonitrile, (meth)acrylates or maleic anhydride, at impact modification with different rubbers or styrene-butadiene block copolymers and at blending with other polymers such as polyphenylene ether (PPE) or polyolefins. 

Enhanced property demands in the packaging sector and also in the electric/ electronic and automotive sectors require improved product properties. Homogeneously miscible blends with, e.g., polyphenylene ether (PPE) combine the excellent processability of the amorphous polystyrene with the thermal stabilty of its blend partners. 

MABS polymers (methyl methacrylate-acrylonitrile-butadiene-styrene) together with blends composed of polyphenylene ether and impact-resistant polystyrene (PPE/PS-I) also form part of the styrenic copolymer product range. Figure 2.1 provides an overview of the different classes of products and trade names. A characteristic property is their amorphous nature, i.e. high dimensional stability and largely constant mechanical properties to just below the glass transition temperature, Tg. 

This review summarizes our work at the University of Bayreuth over the last few years on improving the electret performance of the commodity polymer isotactic polypropylene (Sect. 3) and the commodity polymer blend system polystyrene/polyphenylene ether (Sect. 4) to provide electret materials based on inexpensive and easily processable polymers. To open up polymer materials for electret applications at elevated temperatures we concentrated our research on commercially available high performance thermoplastic polyetherimide resins and synthesized several fluorinaled polyetherimides to identify structure-property relations and to improve further the performance at elevated temperatures (Sect. 5). 

Nonolefinic thermoplastic polymers that in principle may be blended with polyolefins include polyamides (nylons) such as polyamide 6, polyamide 66, polyphenylene sulfide (PPS), polyphenylene ether (PPF), and polyphenylene oxide (PPO) polyesters such as polyethylene terephthalate (PET), polybutylene terephtha-late (PBT), polyethylene naphthalate (PEN), polytrimethylene terephthalate (PTT), polycarbonates, polyethers, and polyurethanes vinyl polymers such as polystyrene (PS), polyvinyl chloride (PVC), polymethylmethacrylate (PMMA), and ethylene... 

S. Stack, 0. O Donoghue, and C. Birkinshaw. The thermal stability and thermal degradation of blends of syndiotactic polystyrene and polyphenylene ether. Polym. Degrad. Stabil, 79(l) 29-36, 2003. 

Polyphenylene ether (PPE) and polystyrene Partially incompatible polymer blends Polyethylene and polyisobutylene Polyethylene and polypropylene (5% PE in PP) Polycarbonate and polybutylene terephthalate... 

The commercial PPO resins were developed by General Electric (Noryl) and defined as modified PPO. Their exact chemical nature is unknown. They may be polymer blends, likely with polystyrene or high-impact polystryene. In Europe PPO is recognized by a more generic name, polyphenylene ether (PPE). 

Polystyrene was immiscible with HDPE, forming coarse domains. Addition of 9% styrene-ethylene-butylene-styrene block copolymer gave much finer domain structure [19]. This compatibilizing effect was also observed in PS -I- polyphenylene ether blends with HDPE, where the styrene blocks of SEBS were attracted to the PS and PPE, improving interfacial adhesion and changing crazing dilation into shear yielding [89]. 

Modified-polyphenylene oxide (or ether) is a blend of high impact polystyrene (PS) and polyphenylene oxide (PPO), plus thermal stabilizers and a triarylphosphate flame retardant. Studies of the mechanism of the flame retardant in modified-polyphenylene oxide have shown some evidence for both solid phase and vapor phase inhibition (4). Indeed, one is always interested to know whether flame retardant action is on the solid or vapor phase. 

Recent work on crystallinity measurements is reported below sulfur containing ether ketones [14], polyethylene glycol [15], polystyrene (PS) [16, 17], (PC) [18], polyphenylene alkene diyls [19, 20], isotactic polypropylene [20, 21], polyethylene [21, 22], polyimide [23], poly(2,5 bis (4-methoxyphenyl) oxycarbonyl styrene [24], polyazomethine esters [25], PET-polybutylene terephthalate blends [26], polycyclohexyl ethylene copolymers [27], polycaprolactone [28], syndiotactic polystyrene [29, 30], polyvinylidene fluoride-trifluorethylene copolymer [30], polyethers [31], isotactic methyl methacrylate [32], soy protein isolate polymers [33], polyamide 6/66 [34], polytrimethylene-2,6-naphthalate [35, 36], PE like polyesters [37], polycyclohexadiene [38], p-dioxolone, L-lactide - polyethylene glycol copolymers [39], ethylene - methacrylic acid copolymers and ionomers [40]. 

---