Naphthalate-based blends

Most blends of polymers are immiscible. Solubility parameter considerations predict that miscibility may be possible when small differences (e.g. 0.5) in 

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Other naphthalate-based polyesters include the butanediol-based analogue, poly(butylene naphthalate) (PEN), as well as copolymers and blends of PET [poly(ethylene terephthalate)] with PEN. 

In addition to the crystal forms, X-ray scattering studies indicate that when unoriented PEN fiber was drawn at 120 °C ( 7 g), a mesophase is generated. In this form, the molecular chains are in registry with each other in the meridional direction but not fully crystallized in the equatorial direction. This conclusion was based on the presence of additional meridional peaks not accounted for by the crystal structure obtained by X-ray scattering. The mesophase is a intermediate phase and its existence is strongly dependent upon the processing conditions consequently, it could have implications with respect to the properties of commercially produced fibers and films, since it appears to be stable and not easily converted to the crystalline form, even at elevated temperature [25, 26], The mesophase structures of PET, PEN and poly(ethylene naphthalate bibenzoate) were compared by Carr et al. [27], The phase behavior of PEN and PEN blends with other polymers has also been studied [28-32],... 

The modification of PET with naphthalene-2,6-dicarboxylic acid and other additional comonomers is a common measure in bottle manufacturing. Copolyesters based on this compound show excellent barrier properties. Such materials can be produced by addition of the desired amount of comonomer during polymer processing or by blending PET with poly(ethylene naphthalate) (PEN). Additionally, PEN can also be modified by other comonomers such as isophthalic acid (IPA) to improve the flow properties and reduce the melting point. The high price of naphthalene dicarboxylic acid is the reason for its limited application. The overall cost may be reduced by using TPA or IPA as comonomers. 

Partial substitution of terephthalate-based polymers with the naphthalate group, in a copolymer or blend form, can provide enhanced properties that are... 

Melt processing has been used also for polymer and polymer blend/silica nanocomposites. In particular, extensive studies are reported for PP [228], PP-based copolymer [229], PE [230], PE-based copolymer [231,232], PS [233-235], PMMA [234,235], PC [234], PC-based copolymer [236], polyethylene naphthalate (PEN) [237], perfluoropolymer [238], PET [239-241], PA [242], polyvinyl acetate (PVAc) [243], co-polyetherester [244], styrene-butadiene rubber [245,246], ethylene vinyl acetate (EVA) [247], PET/PS [248], PLEA [249], and many others. 

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