Polybutylene polymers

Uses Polybutylenes polymer and alkylate gasoline intermediate for butyl and pentyl aldehydes, alcohols, maleic acid, and other organic compounds. 

Polybutylene polymers are prepared by the polymerization of 1-butene using Ziegler-Natta catalysts The molecular weights range from 770,000 to 3,000,000. Copolymers with ethylene are often prepared as well. The chain structure is mainly isotactic and is shown in Fig. 2.13. ... 

Polybutylene polymers slow oystallization rates are helpful in forming hot-melt adhesives with long open times [67]. Besides the hot-melt viscosity, lap shear strength, T-peel, and open time, the shear adhesion failure temperature (SAFT) of the bonded substrate is an inqxntant noperty for evaluating the effectiveness of the adhesive. The polymer MFI plays an inqxntant part in determining the surface tenqterature at whidi shear adhesion fidlure could occur, as can be seen from Fig. 9.75. The top curve represents the SAFT test results with a 0.5-kg load, whereas the bottom curve shows test results with a 1-kg... 

Korcz, W. H., Polybutylene polymers for hot melt adhesives. Adhesive Age, 19-23 (November 1984). 

Degradation of polyolefins such as polyethylene, polypropylene, polybutylene, and polybutadiene promoted by metals and other oxidants occurs via an oxidation and a photo-oxidative mechanism, the two being difficult to separate in environmental degradation. The general mechanism common to all these reactions is that shown in equation 9. The reactant radical may be produced by any suitable mechanism from the interaction of air or oxygen with polyolefins (42) to form peroxides, which are subsequentiy decomposed by ultraviolet radiation. These reaction intermediates abstract more hydrogen atoms from the polymer backbone, which is ultimately converted into a polymer with ketone functionahties and degraded by the Norrish mechanisms (eq. 

Polymerization. Polymerization reactions, which are addition reactions, are used to produce the principal products formed direcdy from butlylenes butyl elastomers polybutylenes and polyisobutylene (see Elastomers, synthetic Olefin polymers). 

In a molded polymer blend, the surface morphology results from variations in composition between the surface and the bulk. Static SIMS was used to semiquan-titatively provide information on the surface chemistry on a polycarbonate (PC)/polybutylene terephthalate (PBT) blend. Samples of pure PC, pure PBT, and PC/PBT blends of known composition were prepared and analyzed using static SIMS. Fn ment peaks characteristic of the PC and PBT materials were identified. By measuring the SIMS intensities of these characteristic peaks from the PC/PBT blends, a typical working curve between secondary ion intensity and polymer blend composition was determined. A static SIMS analysis of the extruded surface of a blended polymer was performed. The peak intensities could then be compared with the known samples in the working curve to provide information about the relative amounts of PC and PBT on the actual surface. 

Polyester, thermoplastic TP polyesters have different grades. Polybutylene tereph-thalate (PBT) a crystalline polymer and an excellent engineering material. It has marginal chemical resistance but resists moisture, creep, fire, fats, and oils. Molded items are hard, bright colored, and retain their impact strength at temperatures as low as — 40°F (-40°C). Uses include auto louvers, under-the-hood electricals, and mechanical parts. 

Polybutylene terephdialate (PBT) has been produced from PET scrap by transesterification widi 1,4-butanediol.1 In die process, classified and cleaned polymer Bake from postconsumer PET bottles is reacted witit 1,4-butanediol in an extruder. PBT is used as an engineering plastic. Ethylene glycol and tetrahydrol uran produced as by-products are recovered by distillation. 

A general methodology has been developed for the treatment of NMR data of polymer mixtures. The methodology is based on reaction probability models and computer optimization methods, resulting in a family of computer programs called MIXCO. The use of MIXCO programs enabled three components to be resolved from NMR tacticity data of fractionated polybutylene. 

More recently, two-state E/B models have been proposed by Chujo and Doi (9.10) for the analysis of polypropylene. Similar E/B models were proposed by Cheng(11) and Asakura, et al(12) for polybutylene. For copolymers, two-state B/B models have been proposed for ethylene-propylene copolymers,(11,13-15) and propylene-butylene copolymers.(11,13) Recently, Cheng(11) generalized these multi-state models and developed computer methodology for the general analysis of such systems. A number of polymer systems were treated. 

As an example, polybutylene is a commercially inq ortant polymer made with Ziegler-Natta catalysts. Such catalysts frequently produce more than one catalytic site, and the resulting polymer is a blend of several homopolymers differing only in propagation statistics. Previously, the two-site E/B model has been used to analyze the tacticity of this polymer.(11,12) Reasonably good fits with experimental data were observed. 

C13-0055. Polybutylene terephthalate, used to make countertops and sinks, has the following stmcture. Draw the stmctural formulas of the monomers from which this polymer is made. 

Polyesters, which are a class of engineering thermoplastics, are found in a wide variety of applications including carbonated drink bottles, fibers for synthetic fabrics, thin films for photographic films and food packaging, injection molded automotive parts, and housings for small appliances. In this chapter, we svill explore the synthesis of this class of polymers. We will also look at the typical properties and end uses for the most common of these resins, polyethylene terephthalate and polybutylene terephthalate, which are commonly known as PET and PBT, respectively. 

Polyesters form via a condensation reaction between a dicarboxylic acid and a dialcohol to create an ester linkage, as shown in Fig. 24.1. By far, the two most common polyesters are polyethylene terephthalate and polybutylene terephthalate, the chemical structures of which are shown in Fig. 24.2. These two polymers differ from one another by the length... 

In addition to the desired polymerization reaction, the dialcohol reactants can participate in deleterious side reactions. Ethylene glycol, used in the manufacture of polyethylene terephthalate, can react with itself to form a dialcohol ether and water as shown in Fig. 24.4a). This dialcohol ether can incorporate into the growing polymer chain because it contains terminal alcohol units. Unfortunately, this incorporation lowers the crystallinity of the polyester on cooling which alters the polymer s physical properties. 1,4 butanediol, the dialcohol used to manufacture polybutylene terephthalate, can form tetrahydrofuran and water as shown in Fig. 24.4b). Both the tetrahydrofuran and water can be easily removed from the melt but this reaction reduces the efficiency of the process since reactants are lost. 

Both polyethylene terephthalate and polybutylene terephthalate exhibit partial crystallinity in the solid state. The molecular weight of the polymer and the time permitted for cooling define the degree of crystallinity of the polymer. Very slow cooling results in high crystallinity and opacity, while fast quenching creates low crystallinity, high clarity material. 

Rubber-like materials now superseding the traditional mastics and putties used in the building industry. Such sealants (also termed mastics) are based on butyl rubber, liquid polysulphides, silicone rubbers, polybutylene, nitrile rubbers and plasticised vinyl polymers. SEBS... 

We previously reported that brominated aromatic phosphate esters are highly effective flame retardants for polymers containing oxygen such as polycarbonates and polyesters (9). Data were reported for use of this phosphate ester in polycarbonates, polyesters and blends. In some polymer systems, antimony oxide or sodium antimonate could be deleted. This paper is a continuation of that work and expands into polycarbonate alloys with polybutylene terephthalate (PBT), polyethylene terephthalate (PET) and acrylonitrile-butadiene-styrene (ABS). 

Figure 6.2 The polyesteramide structure proposed by Gaymans and co-workers E, ester group A, amide group [21]. Reprinted from Polymer, 38, van Bennekom, A. C. M. and Gaymans, R. J., Amide-modified polybutylene terephthalate structure and properties, 657-665, Copyright (1997), with permission from Elsevier Science...

Song, K. and White, J. L., Formation and characterization of cast and biaxi-ally stretched polybutylene terephthalate film, Polym. Eng. Sci., 38, 505-515 (1998). 

Hobbs, S. Y. and Pratt, C. F., The effect of skin-core morphology on the impact fracture of polybutylene terephthalate, J. Appl. Polym. Sci., 19, 1701-1722 (1975). 

Borman, W. F. H., Molecular weight-viscosity relationships for polybutylene terephthalate,./. Appl. Polym. Sci., 22, 2119-2126 (1978). 

Cheng, Y.-Y., Brillhart, M., Cebe, P. and Capel, M., X-ray scattering and thermal analysis study of the effects of molecular weight on phase structure in blends of polybutylene terephthalate with polycarbonate, J. Poly. Sci., Polym. Phys., 34, 2953-2965 (1996). 

Hamilton, D. G. and Gallucci, R. R., The effects of molecular weight on polycarbonate-polybutylene terephthalate blends, J. Appl. Polym. Sci., 48, 2249-2252 (1993). 

Pellow-Jarman, M. and Hetem, M., The effect of the polybutylene terephthalate constituent on the reactions occurring in PBT-polycarbonate polymer blends below their decomposition temperature, Plast. Rubber Composites Proc. Appl., 23, 31-41 (1995). 

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