Poly-2,6-dimethylphenylene oxide PPO

We have recently demonstrated the synthesis of poly(2,6-dimethylphenylene oxide) (PPO) via oxidative coupling in a C02 continuous phase (see Scheme 7) [76]. These reactions proceeded at 345 bar and either room temperature or... 

A series of Japanese patent applications concerns addition of BPA/DC to poly(2,6-dimethylphenylene oxide) (PPO). Electroinsulating coatings with elevated heat resistance were obtained from PPO and BPA/DC [43]. As a rule, maleimide monomers are used together with BPA/DC. According to [44], the following reaction (Scheme 10) between BPA/DC and maleimide takes place ... 

Touring the last decade, catalyzed oxidative coupling has gained wide-spread interest as a novel and general polymerization method. Various polymer systems of scientific and commercial interest have been prepared by this novel technique. Such polymer systems include polyphenylene oxides) (9, 13, 25), of which poly(2,6-dimethylphenylene oxide) (PPO) is produced commercially polyphenylenes (21) poly-... 

First experiments which focused on the variation of the conformational properties have been performed by Brown et al. [240], who studied the role of the interactions between matrix and brush polymers (enthalpy driven brush swelling, see Eq. 59). They used a series of polystyrene (PS)-poly(methyl methacrylate) (PMMA) symmetric diblock copolymers with different blocks labeled by deuterium, placed at the interface between PMMA and poly(2,6-dimethylphenylene oxide) (PPO) homopolymers. A double brush layer was created with PMMA blocks dangling into (neutral) PMMA homopolymer and PS blocks immersed in favorably interacting PPO melt (x=Xps/ppo<0)- The SIMS profiles obtained showed that the PS side of the block copolymer is stretched by at least a factor of 2 with respect to the PMMA side. 

Poly(2,6-dimethylphenylene oxide) (PPO) is synthesized via oxidative coupling in a CO2 continuous phase (43). The reactions proceed at 34.5 MPa (345 bar) and at either room temperature or 40° C for 20 h using a CuBr/amine/02 catalyst system (eq. (10)). PPO with yields as high as 83% andMn up to 1.7 x 10 g/mol were precipitated. Small molecule amines (pyridine and dimethylethylamine) and CO2-soluble polymeric amines (block copolymers of FOA and either 4-vinylpyridine or DMAEA) were used in the reaction. 

Polystyrene is miscible with poly(2,6-dimethylphenylene oxide), PPO. The commercial composition actually uses HIPS blended with PPO, again resulting in a very tough product. A blend of poly(vinylidene fluoride) with poly(methyl methacrylate) imparts both light stability and gasoline resistance, making it useful for coating automotive parts. 

In miscible binary blends, amorphous homopolymers are completely accommodated within amorphous layers of the lamellar morphology formed after the crystallization of crystalline homopolymers. Stein et al. [51], for example, observed the lamellar morphology formed in a miscible blend of PCL and poly(vinyl chloride) (PVC) using SAXS as a function of composition. They found that PVC existed in amorphous layers of the lamellar morphology to yield a linear increase in the amorphous layer thickness with increasing PVC composition, whereas the crystalline layer thickness remained constant irrespective of composition. Wenig et al. [52] obtained similar results for a miscible blend of poly(2,6-dimethylphenylene oxide) (PPO) and isotactic polystyrene (iPS). However, a different result was reported for a miscible blend of iPS and atactic polystyrene [53], where the amorphous layer thickness was almost constant irrespective of composition. Stein et al. [51] explained this difference in... 

PPO PolyCphenylene oxide) poly(2,6-dimethylphenylene oxide) XLPE, XPE Cross-linked polyeAiylene ... 

Prest and Portermeasured the viscoelastic properties of several poly(2,6-dimethylphenylene oxide)/polystyrene (PPO/PS) blends at T= 220 C. 

In 1956, Allan S. Hay of the General Electric Company discovered a convenient catalytic oxidative route to poly(2,6-dimethylphenylene ether), or PPE. This amorphous polymer exhihited exceUent hydroljdic stability, an extremely high glass transition temperature [Tg = 419°F (215°C)], outstanding electrical properties over a wide temperature range, low density relative to other engineering thermoplastics, and a high melt viscosity. The polymer was introduced commercially in 1964 under the PPO trademark [1, 2]. 

Solvent resistant laminates for printed circuits were manufactured by coating of copper foil with a solution of PPO, BPA/DC, bis(4-maleimidophenyl) ether and Zn octoate in toluene the coated foil was laminated with PPO-impregnated glass fabric [47]. Similar result was achieved by the modification of PPO with polyfunctional cyanates or maleimides, liquid polybutadiene and a polymerization catalyst [48], A solvent and heat resistant composition for printed circuits consists of copoly [(2,6-dimethylphenylene)-(2,3,6-trimethylphenylene)]oxide, maleic anhydride grafted poly-1,2-butadiene, bis(4-maleimidophenyl)methane, BPA/DC and toluene. BPA/DC prepolymer may be used instead of the monomer [49]. 

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