Poly PETP

LDPE Low-density polyethylene PET, PETP Poly(ethylene terephthalate)... 

Notes Cellulose (Whatman) PTMSP, poly(trimethyl silyl propine) PS, polystyrene PP, polypropylene PE, polyethylene PA 66, polyamide 66 PA 6, polyamide 6 PVP, poly(vinyl pyrrolidone) PPO, poly(2,6-dimetyl-l,4-phenylene oxide) PMMA, poly(methyl methacrylate) PETP, polyethylene terephthalate) Irganox 1010 is a Ciba anti-oxidant. 

Figure 6 (A) Non-isothermal chemiluminescence runs for oxidation of polystyrene (PS), polyethylene terephthalate) (PETP) and polyfmethyl methacrylate) (PMMA), in oxygen, heating rate 2.5°C/min. (B) Non-isothermal chemiluminescence runs for oxidation of polypropylene (PP), polyamide 6 (PA 6), poly(vinyl pyrrolidone) (PVP), polyethylene (PE) and polyamide 66 (PA 66), in oxygen, heating rate 2.5°C/min.

Blends of poly (ethylene terephthalate) (PETP) and polypropylene (PP) with different rheological properties were dry blended or compounded, and extrusion foamed using both physical blowing and chemical agents, and the foam properties compared with those of foam produced from the individual components in the absence of compatibilisers and rheology modifiers. The foams were characterised by measurement of density, cell size and thermal properties. Low density foam with a fine cell size was obtained by addition of a compatibiliser and a co-agent, and foamed using carbon dioxide. The presence of PP or a polyolefin-based compatibiliser did not effect... 

Working with a solution is needed for polymers which above their melting point would degrade (example aromatic polyamide fibres such as Kevlar and Twaron). For fibres the removal of the solvent is not too problematic. In e.g. injection moulding applications solvents caimot be used here thermotropic LCP s have to be used. Since these would degrade during processing, they are diluted by copolymerisation (example poly-hydroxy-benzoic acid - co - PETP)... 

The heat conductivity of amorphous poly(ethylene terephthalate) at room temperature is 0.218 J (m s K)-1. Calculate the heat conductivity of semi-crystalline PETP at a degree of crystallinity of 0.40. 

Estimate the solubility and the heat of solution (sorption) of oxygen in poly(ethylene terephthalate) (PETP), both in the quenched amorphous glassy state and in the semicrystalline state (xc = 0.45). 

An interesting example of the difference in drawing behaviour between amorphous and crystalline yam is the drawing of crystalline poly(ethylene terephthalate). It is often stated that crystalline PETP cannot be drawn. It is tme that the material breaks if drawn at a temperature of 80 °C, which is a drawing temperature normal for the amorphous polymer. Mitsuishi and Domae (1965), however, were able to draw crystalline PETP to a draw ratio of 5.5 at a temperature of 180 °C. 

On curves DTA initial PETP - fibres and modified hexsaazocyclanes (Figure 5), the peak of fusion represents the area having one maximum that confirms the assumption made earlier of dependence of temperature of fusion from a morphological structure of poly mer. 

PES PESF PETP PIGMA VAC VC) polylethylene succinate) poly(ethersulfone) polylethylene terephthalate) polylglycidyl methacrylate-co-vinyl acetate-co-vinyl chloride)... 

Polyesters form a large class of commercially important polymers. A typical polyester is poly(ethylene terephthalate) (PETP), the largest volume synthetic fiber. It is also used as film (mylar) and in bottle applications. We have already discussed in the preceding section one of the routes for the preparation of PETP. The traditional route for the production of commercial PETP is through two successive ester interchange reactions, as shown below ... 

As noted earlier, linear polymers are obtained from condensation polymerization when the functionality of the reactants is 2. Two cases may be considered. Some commercial examples of step-growth polymerization are illustrated in Figure 6.3. Reactions A and B are two routes (esterification and ester interchange) for preparing the same compound [poly(ethylene terephthalate), PETP], Reaction C is... 

Poly(ethylene terephthalate) PETP Poly(vinyl ehloride) PVC... 

Figure 5-4. X-Ray intensity as a function of Bragg angle of amorphous (—) and crystalline (—) poly(ethylene terephthalate). The amorphous PETP was prepared by precipitation of the polymer from a solution in phenol-tetrachloroethane (1 1) with glycerol. Crystalline PETP was prepared by annealing (from A. Jeziorny and S. Kepka).

The apparatus is described and details given of its use with PETP homopolymer, PS/poly(vinyl methyl ether) miscible blend and styrene-styrenesulphonic acid copolymer/ethyl acrylate-4-vinylpyridine copolymer ionomer blend with ionic interactions. Orientation and relaxation curves were obtained for all three samples. It is concluded that the technique is very efficient for obtaining curves with high precision. For these three systems, the relaxation rate increases with temperature. 

For PETP, a reorientation as a function of time was observed. This phenomenon is dependent on temperature and draw ratio, and is probably due to the crystallisation of the sample. For the PS/poly(vinyl methyl ether) blend, the addition of poly(vinyl methyl ether) to the blend increased the orientation of the PS chains during the stretching. Forthe ionomer blends, the orientation of both types of chain was higher when the ionic content increased. 4 refs. 

Poly(ethylene terephthalate) (PETP) produces a relatively hydrophobic fiber that is readily soiled by oil. The soiling tendency can be eliminated by grafting 0.5 % of acrylic acid onto the fiber with the aid of ionized gases or by partial hydrolysis of the surface (whereby free —COOH groups are produced). Incorporation of 5 % adipic acid into the polymer reduces the crystallinity and thereby improves the dyeability. Incorporation of small amounts of sulfonated terephthalic acid produces anionic sites for cationic dyestuffs. 

Construction components of poly(ethylene terephthalate) absorb practically no moisture. These components are hard and rigid, exhibit very little wear and tear, show very little creep, and tolerate high mechanical loads. These physical properties, together with the very small linear coefficient of expansion, make PETP ideal for high precision cog wheels and for moving components in, for example, sewing machines. 

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