Polyethylene terephthalate effect additives

Aromatic polyphosphonates have been found to be especially effective flame retardant additives for polyester compositions (j), 1, 8), especially for polyethylene terephthalate. 

It was revealed earlier [2], that hexsaazocyclanes additives cause temperature reduction of polyethylene terephthalate fusion, i.e. they have a plasticization effect on polymer. 

Komolprasert V, McNeal TP, Begley TH. Effects of gamma- and electron beam irradiation on semi-rigid amorphous polyethylene terephthalate copolymers. hood Addit Contain 2003 20(5) 505 17. 

However, one of our customers (27) found it to be an effective additive to polyethylene terephthalate in order to increase the strength and reduce the striation when the polymer was extruded into polyester film. This certainly was an unexpected commercial success. I would regard this commercial success as pure luck on our part. After all. Dr. Walsh s group designed the compound to be a flame retardant. 

The volume resistivity of an unplastlclzed pottant material such as EVA is 10 ohm-cm. The module current leakage at 1.5 kV with EVA is an order of magnitude lower than with plasticized PVB at 25-30°C and there appears to be no rise in leakage at 50-60°C. (See Figure H and Table I.) Similarly, the current leakage of modules containing plasticized PVB can be blocked by the Insertion of an additional high volume resistivity layer such as polyethylene terephthalate film as discussed below, which is resistant to the solvation effect of dlester plasticizers. 

An important prerequisite for light-induced degradation is that the plastic absorb solar UVR or visible radiation as only the absorbed light can degrade the plastic. Polyolefins in theory do not have chromophores that can absorb light effectively, but trace impurities in the plastic and some of the additives in the material act as good chromophores. Plastics such as PS, polycarbonate (PC), and polyethylene terephthalate (PET), have aromatic functional groups that absorb UV radiation. 

Descriptors "Additives Polyvinyl chlorides Polypropylenes Polyethylene terephthalates Composition effects Desorption Stabilizers (agents) Carbon dioxide lasers Laser ablation Antioxidants... 

PET (polyethylene terephthalate) has poor affinity for traditional shell compositions, but the use of hydroxy-containing compositions can aid in allowing the use of core-shell type additives for effective toughening [134] (Fig. 14-13). 

The paper has reviewed recent and current studies of the adhesion and friction of polyethylene-terephthalate monofilaments. The influence of surface topography and various liquids on these processes has been described. In addition, short descriptions of the dynamics of sliding and the effects of solid films have been given. 

Li et al. reported that immiscible high-density polyethylene (HDPE)/ poly(ethylene terephthalate) (PET) blends, prepared by means of melt extrusion with ethylene-butyl acrylate-glycidyl methacrylate (EBAGMA) terpoly-mer as a reactive compatibilizer, can exhibit shape memory effects [32]. They observed that the compatibilized blends showed improved shape memory effects along with better mechanical properties as compared to the simple binary blends. In the blend, HDPE acts as a reversible phase, and the response temperature in the shape recovery process is determined by of HDPE. The shape-recovery ratio of the 90/10/5 HDPE/PET/EBAGMA blend reached nearly 100%. Similar behavior was observed for immiscible HDPE/ nylon 6 blends [33]. The addition of maleated polyethylene-octene copolymer (POE-g-MAH) increases compatibility and phase-interfacial adhesion between HDPE and nylon 6, and shape memory property was improved. The shape recovery rate of HDPE/nylon 6/POE-g-MAH (80/20/10) blend is 96.5% when the stretch ratio is 75%. 

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