Poly-butene-terephthalate

Multilayered materials owe their properties and behavior to the properties of and the interactions between the components (5). Each of the two or more components contributes its particular property to the total performance of the multilayered material. For example, in Pouch 1, Table II, the aluminum foil provides high oxygen and water vapor permeability resistance, poly (ethylene terephthalate) provides structural strength and stiffness, and the ethylene-butene copolymer provides a heat sealable layer. If the components of the multilayered materials interact then the whole would be something different than the sum of its parts. In other words, the properties of the components of the multilayered materials are not independent of one another but rather are interdependent. 

Bond strength data for four multilayered materials is shown in Table V. In each case the data is for the bond between the food-contacting layer and its adjacent layer. In Pouch 1, it is the bond between ethylene-butene copolymer and aluminum foil in Pouch 2 between ethylene-butene copolymer—polyisobutylene blend and aluminum foil in Pouch 3 between ethylene-butene copolymer and polyiminocaproyl and in Pouch 4 between ethylene-butene copolymer and poly(ethylene terephthalate). Bond strength increased in the four multilayered materials after the irradiation treatment. 

The superior properties of polypropylene terephthalate) (PPT) polymer and fibers over the chemically analogous poly(ethylene terephthalate) (PET, used for soda bottles) and poly(butylene terephthalate) (PBT) have been well known for several decades PPT fibers are much more elastic and less brittle than PET and offer better recovery from stretching than PBT they are also easier to dye than either PET or PBT. Compared to the intermediate for PET, ethylene glycol, which is available inexpensively from ethylene oxide, and to that for PBT, butanediol, likewise available inexpensively from butene or butadiene, the intermediate for PPT, 1,3 propanediol (1,3-PPD or PDO), was not - and on a large scale is still not - available. Three processes, two chemical ones and one biotechnological, compete to change this situation (Figure 20.10). 

The list of polymers known to respond satisfactorily to permanganic etching is now long and continually growing. It consists of linear and branched polyethylene, four isotactic polyolefins (polypropylene, polystyrene, poly(4-methylpentene-l) and poly(butene-l)), related atactic polymers, poly(vinylidene fluoride) (hereafter denoted PVF2), PEEK, and poly(ethylene terephthalate) (PET), together with various copolymers and others such as ethylene propylene rubbers and ethylene-propylene-diene (EPDM) terpolymer. 

Fig. 5. Boson peak energy as a function of monomer mass for amorphous polymers and as a function of molecular mass for organic molecular glasses. Amorphous polymers polyethylene (PE) [29], poly(vinyl alcohol) (PVA) [152], cis-1,4-polyhutadiene (PB), polyisobutylene (PIB), frans-1,4-polychloroprene (PCP), atactic polyst ene (PS), atactic poly(methyl methacrylate) (PMMA), poly(ethylene terephthalate) (PET) [30, 34], atactic polypropylene (a-PP) [95],polyisoprene with deuteratedmethyl group (PIP-dj) [36],polycarbonate (PC) [91],polyimide (AURUM) [39]. Molecular glasses propylene (P), 1-butene (B), 3-methyl pentane (MP),ortho-terphenyl (OTP),ethylbenzene (EB) [38]...

The half-time of primary crystallisation, ti, shows a similar dependence on tenperature and polymer-filler interaction energy (see Fig. 5). To find ti, it was asstmed that the contribution of the slow secondary crystcillisation process to the primary portion of the overall crystallisation curve was negligible. Thus ti was half the value of the time at the intersection point (see curve 3, Fig. 3), using the extrapolation method of Vidotto et al (28) for the crystallisation of isotactic poly butene-1, and used Ey Groeninckx et al (11) for the crystallisation of poly(ethylene terephthalate). 

Poly(l,4-benzamide) (PBA), 13 371 Poly(1-butene) (PB), 4 429. See also Blown PB film Isotactic PB resins Isotactic poly(l- butene) (PB) PB entries Pipe-grade PB resin Syndiotactic poly(1-butene) (PB) mechanical properties of, 20 418 polymerization processes for, 20 424-425 uses of, 20 430-431 commercial manufacture of, 20 429 Poly-1-olefins, regioregular, 26 513 Poly(l,4-butylene terephthalate) (PBT), 10 188... 

The oxidation stability of poly( butylene isophthalate-co-terephthalate) copolyesters has been shown to decrease steadily with isophthalate unit content [26]. As expected, GC-MS analyses show that oxidation takes place mainly in the butylene units, through the same mechanism as before. Small-molecule products of a copolyester containing 25 mol% isophthalate included THF, butyrolactone, 3-buten-2-one, 2-propenal, and various other cyclised and carbonyl fragments, along with acetic acid. As has been observed for most polyesters, thermal and thermo-oxidative reactions occur simultaneously, and the lower stability of butylene-isophthalate units is most probably responsible for the lower overall stability of copolymers containing this structure, even under the oxidation conditions used. 

Some crystalline polymers, e.g., polyolefin polymers such as poly-(ethylene), poly(propylene) (PP) and poly(l-butene), and polyfester) polymers such as polyfethylene terephthalate), and poly(amide) (PA) polymers have a slow rate of crystallization after heat forming. Consequently, the molding cycle when they are processed is too long, and as crystallization proceeds even after molding is complete, the molded product is sometimes deformed. In addition, there is the disadvantage that these crystalline polymer compound materials formed large spheroid crystals, so their mechanical strength and transparency is poor. 

---