Polyester resins composites

Diacyl peroxides are used in a broad spectmm of apphcations, including curing of unsaturated polyester resin compositions, cross-linking of elastomers, production of poly(vinyl chloride), polystyrene, and polyacrjlates, and in many nonpolymeric addition reactions. 

Aromatic diacyl peroxides such as dibenzoyl peroxide (BPO) [94-36-0] may be used with promoters to lower the usehil decomposition temperatures of the peroxides, although usually with some sacrifice to radical generation efficiency. The most widely used promoter is dimethylaniline (DMA). The BPO—DMA combination is used for hardening (curing) of unsaturated polyester resin compositions, eg, body putty in auto repair kits. Here, the aromatic amine promoter attacks the BPO to initially form W-benzoyloxydimethylanilinium benzoate (ion pair) which subsequentiy decomposes at room temperature to form a benzoate ion, a dimethylaniline radical cation, and a benzoyloxy radical that, in turn, initiates the curing reaction (33) ... 

Ketone Peroxides. These materials are mixtures of compounds with hydroperoxy groups and are composed primarily of the two stmctures shown in Table 2. Ketone peroxides are marketed as solutions in inert solvents such as dimethyl phthalate. They are primarily employed in room-temperature-initiated curing of unsaturated polyester resin compositions (usually containing styrene monomer) using transition-metal promoters such as cobalt naphthenate. Ketone peroxides contain the hydroperoxy (—OOH) group and thus are susceptible to the same ha2ards as hydroperoxides. 

Mechanical Properties. The performance of various polyester resin compositions can be distinguished by comparing the mechanical properties of thin castings (3 mm) of the neat resin defined in ASTM testing procedures (15). This technique is used widely to characterize subtle changes in flexural, tensile, and compressive properties that are generally overshadowed in highly filled or reinforced laminates. 

The surface energy of fibers is closely related to the hydrophilicity of the fiber [38]. Some investigations are concerned with methods to decrease hydrophilicity. The modification, of wood cellulose fibers with stearic acid [43] hydrophobizes those fibers and improves their dispersion in polypropylene. As can be observed in jute-reinforced unsaturated polyester resin composites, treatment with polyvinylacetate increases the mechanical properties [24] and moisture repellency. 

Polyester polyols, 25 464 468 Polyester resin(s), 11 302 coating resins, 7 104-106 cyclopentadiene and dicyclopentadiene applications, 8 230 flammability of, 20 115-116 properties in powder coating, 7 43t standard test methods for, 20 11 It unreinforced, 10 187t weathering of, 20 116 Polyester resin-based powder coatings, organic titanium compounds in, 25 125 Polyester resin composites, 26 762-763 Polyester resin formulations ingredients of, 20 96t unsaturated, 15 511-512 Polyesters, 10 185-189, 497 12 655-656. See also Thermoplastic polyesters Unsaturated polyesters acid resistance of, 20 7-8 antioxidant applications, 3 121 aromatic ionic, 23 722 based on 1,4-cyclohexanedimethanol, 12 674-675... 

Fig. 6.6. Fracture toughness of steel wire-polyester resin composites (f = 0.1) as a function of fiber length, ( (O) aligned wires (A) randomly oriented wires. After Helfet and Harris (1972).

A new type of solid propint prepd by treating NH4CIO4 + polyester resin composite propint with NG, MeN02 or 0(CH2CH20N02)2]... 

AMMONIUM PERCHLORATE - 22 2% POLYESTER RESIN COMPOSITE PROPELLANT... 

C.A.Thomas, USP 2742672 (1956) CA 50, 11018-20 (1956) (Comp proplnt prepd by coating each grain of finely divided Amm picrate-Na nitrate with liq thermosetting resin, pressure molding curing) 5)G.S.Sutherland "The Mechanism of Combustion of an Ammonium Perchlorate Polyester Resin Composite Propellant , Princeton Univ, New Jersey (1956), 233 6)A.J.Zaehringer, "Solid Propellant... 

About one-half of the phthalic anhydride production is consumed for the preparation of plasticizers, mostly for the various flexible grades of poly(vinyl chloride). The remainder is roughly split between alkyd resin preparation used for many types of surface coatings, and for polyester resin composites with fiberglass reinforcement, the so-called fiberglass resins used in boats and other sporting equipment as well as for corrosion-resistant vessels and ducts used in chemical processing, some automotive parts, and as a convenient means of field repair of many of these items. 

Owen MJ, Rice DJ. Biaxial strength behavior of glass fabric-reinforced polyester resins. Composites 1981 12(l) 13-25. 

D Short, A W Stankus and J Summerscales, Woven glass-fibre reinforced polyester resin composites exposed to the marine environment . Proceedings 1st International Conference Testing, Evaluation and Quality Control of Composites, Guildford, September 1983. Butterworth Scientific, Guildford, 1983,... 

Features Improves str. as glass fiber size composite in reinforced polyester composites enhances initial wet str. of reinforced polyester resin composites enhances wet elec, props, of many min.-filled and reinforced composites... 

Uses Med.-temp. initiator for polymerization of vinyl monomers and the curing of styrene-unsaturated polyester resin compositions crosslinking agent for unsat. polyesters catalyst in premix polyester BMC, SMC Manuf./Distiib. Akzo Nobel http //www.akzonobel.com] Atofina http //www.atofinachemicals.com] Aztec Peroxides Norac http //www.norac.com Trade Name Synonyms Aztec TBPEH t[Aztec Peroxides] Aztec TBPEH-30-AL t[Aztec Peroxides] Esperox 28 [Crompton/Olefins Styrenics] Luperox 26 [Atofina SA http //www.atofina.com] Atofina http //www.atofinachemicals.com]] Perbutyl O t[NOF http //www.nof.co.jp]... 

Figures 4.4 to 4.10 give design charts, derived from the Halpin Tsai equations, for typical E-glass/polyester resin composite laminae, using the material properties given in Table 4.6. For the purposes of generating the graphs it has been assumed that the fibres and matrix are isotropic.

Varma IK, Ananthakrishnan SR, Krishnamoorthy S (1989) Composites of glass/modified jute fabric and unsaturated polyester resin. Composites 20 383-388... 

Yatsuka, T, et al. (2003) Polyester resin compositions and producing process thereof, PCT Int. Appl., WO 2003066734. 

M., Galina, H., W6jcik, Z., Mental, Z., Krawczyk, B., and Szczepanowska, M. (2000) Thixotropic unsaturated polyester resin composition of improved stability and method of obtaining same. Polish Patent 178 900. 

The surface energy of fibres is closely related to the hydrophility of the fibre. Some investigations are concerned with methods to decrease hydrophility. The modification of wood-cellulose fibres with stearic acid [49] causes those fibres to become hydrophobic and improves their dispersion in PR As can be observed in jute reinforced unsaturated polyester resin composites, treatment with polyvinylacetate increases the mechanical properties [50] and moisture repellence. Silane coupling agents may contribute hydrophilic properties to the interface, especially when amino-functional silanes, such as epoxies and urethane silane are used as primers for reactive polymers. The primer may supply much more amine functionality than can possibly react with the resin at the interphase. Those amines, which could not react, are hydrophilic and therefore responsible for the poor water resistance of the bonds. An effective way to use hydrophilic silanes is to blend them with hydrophobic silanes such as phenyltrimethoxysilane. Mixed siloxane primers also have an improved thermal stability, which is typical for aromatic silicones [48]. 

As a second example, the DOT SP-4877 nitrate shipping container tem also been evaluated using hand calculations. This container is basically a steel outer drum filled with vermiculite. The fissile material is contained in a polyethylene bottle which in turn is doubly bagged and placed in a cadmium-wrapped stainless-steel pressure vessel. A 2-in.-thick polyethylene-polyester resin composite surrounds the cadmium-wrapped pressure vessel. 

A. Damusis and K. C. Frisch, Flexibilized Polyester Resin Compositions Containing Polyurethanes Modified with Vinyl Monomers and Process Therefore, U.S. Pat. 3,448,172 (1969). Polyester/polyurethane grafted semi-SINs. 

Rot K, Huskic M, Makarovic M, Mlakar T L, Zigon M (2001) Interfacial effects in glass fibre composites as a function of unsaturated polyester resin composition Composites Part A, 32(3 ), 511-516. 

A liquid-crystalline polyester resin composition is designed by incorporating a liquid-crystalline polyester obtained by polymerizing monomers of an aromatic hydroxycarboxylic acid in the presence of an imidazole compound. The composition also includes a mica (50-100 phr) having a volume average particle diameter of 40 pm or less and a specific surface area of 6 m /g or less. The liquid-crystalline polyester resin composition has melt fluidity sufficient to be molded into a connector having an ultra-thin wall section. The coimector, thus molded, has sufficiently suppressed warp and sufficient soldering resistance [171]. 

YFukuhara, H.Yamauchi, Liquid Crystalline Polyester Resin Composition and connector using the same. Assigned to Sumitomo Chemical Company Limited, US Patent application number 20100163796, July 01,2010. 

Baley, C., Busnel, F., Grohens, Y., and Sire, O. (2006). Influence of ehemieal treatments on sur-faee properties and adhesion of flax fiber-polyester resin. Composites Part A Applied Science and Manufacturing 37(10), 1626-1637. 

The use of fiber reinforced unsaturated polyester resin composites in the form of sheet molding compound (SMC), bulk molding compound (BMC) and preform molding exceeded 475 000 tons (approximately one billion pounds) in North America and Europe in 1995. Many applications were in the transportation industry such as automotive body panels, truck components and semi-structural parts (Table 1). Other applications are in sanitary ware (bathtubs, showers, sinks), applicances, business machines and electrical components. 

The versatility of unsaturated polyester resin compositions, properties, and fabrication techniques, the design flexibility that can be achieved, and the relatively easy and economical mass production capability and new developments may be further understood and demonstrated by several other good articles and texts. Extensive patent literature, which is... 

Chemical resistance of glass fiber-reinforced polyester resins depends in particular on polyester resin composition, composition and the amount of monomers used, glass composition, laminar structure, the ratio of resin to glass content in individual layers and, last but not least, on processing [32],... 

As described earlier, the use of organosilanes grew from work sponsored by the US Air Force to find products that performed better than the original chrome complexes in glass fiber reinforced unsaturated polyester resin composites. The first success was achieved with vinyl trichlorosilane and its mixtures with allyl alcohol. The unsaturation provided the polymer reactive functionality while the chloro-groups provided the fiber reactive ones. The fiber reactivity comes about by hydrolysis of the chloro-groups to form silicon hydroxyls, which are then able to condense with surface hydroxyls, as shown in the following simplified reaction sequence. 

---