Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Embedding in polyesters

These qualities are highly desirable, and today about 3 billion pounds (1.4 billion kg) of synthetic composites are produced in the United States each year. These products are manufactured at about 2,000 plants that employ more than 150,000 people. About two-thirds of these composites are made from glass fiber embedded in polyester or vinyl ester plastics. The remaining third of composites include a large variety of mixtures. [Pg.20]

Figure 9.5 illustrates typical CLP curves for different lignocellulosic fiber embedded in polyester matrices. [Pg.250]

Daimler Chrysler has been increasing its research and development in flax-reinforced polyester composites for exterior applications for a number of years now [80]. Mercedes also used jute-based door panels in its E-class vehicles in 1996 [81]. Cotton fibres embedded in polyester matrix were used in the body of the East German Trabant car [82]. Some other applications are on Mercedes A and S class mamade from different bio-fibre-reinforced composites [83], Lotus manufactured Eco Elise bodyworks which contains hemp fibres, while sisal fibres are used for interior trimmings while the inner door panels for the BMW 7 Series contain 70% of sisal fibres. Plant fibre-reinforced polylactic acid composites with improved rigidity and reduced processing times have been applied in the Toyota Lexus HS250h hybrid vehicle recently. [Pg.694]

Until quite recently, the structural shapes of pultruded profiles have been copied from steel construction, usually reproducing thin-walled open (I, H, L, C) or tubular (square, rectangular, circular) cross-sections. Figure 9.8 shows the most typical shapes of the so-called first-generation profiles, which are normally composed of glass fibres embedded in polyester or vinylester based resin matrix - GFRP pultruded profiles. [Pg.226]

The FRP rebars are generally manufactured by the pultrusion technique from thermosetting resins such as continuous carbon, glass or aramid fibres embedded in polyester, vinylester or epoxy matrix (Nanni, 1997 ACI, 1996 Pilakoutas, 2000 Bank, 2006). Their geometric cross-sections are typically round, square or rectangular and have smooth surfaces these must be modified to improve the bond characteristics between the concrete and the rebar. The improvements in bond characteristics are effected by forming ... [Pg.613]

Plants were probably the first to have polyester outerwear, as the aerial parts of higher plants are covered with a cuticle whose structural component is a polyester called cutin. Even plants that live under water in the oceans, such as Zoestra marina, are covered with cutin. This lipid-derived polyester covering is unique to plants, as animals use carbohydrate or protein polymers as their outer covering. Cutin, the insoluble cuticular polymer of plants, is composed of inter-esterified hydroxy and hydroxy epoxy fatty acids derived from the common cellular fatty acids and is attached to the outer epidermal layer of cells by a pectinaceous layer (Fig. 1). The insoluble polymer is embedded in a complex mixture of soluble lipids collectively called waxes [1], Electron microscopic examination of the cuticle usually shows an amorphous appearance but in some plants the cuticle has a lamellar appearance (Fig. 2). [Pg.5]

Besides DNA adsorption driven by a positive potential (electrostatic adsorption) DNA was also wet-adsorbed at an open circuit on a home-made polystyrene-based carbon ink [110]. This ink was prepared by a 2 3 mixture of polystyrene and graphite particles in mesitylene, and then printed on a polyester film. DNA was wef-adsorbed over the ink at 37 °C overnight. The nature of the electrode surface (graphite particles embedded in a polystyrene... [Pg.29]

Fiber-reinforced composites contain strong fibers embedded in a continuous phase. They form the basis of many of the advanced and space-age products. They are important because they offer strength without weight and good resistance to weathering. Typical fibers are fiberous glass, carbon-based, aromatic nylons, and polyolefins. Typical resins are polyimides, polyesters, epoxys, PF, and many synthetic polymers. Applications include biomedical, boating, aerospace and outer space, sports, automotive, and industry. [Pg.256]

Figure 2.40 GRP consists of glass fibres (rod shapes) embedded in plastic, in this case polyester. Figure 2.40 GRP consists of glass fibres (rod shapes) embedded in plastic, in this case polyester.
Since about 1950 polymer-bonded (or plastic-bonded) explosives (PBX) have been developed in order to reduce sensivity and to facilitate safe and easy handling. PBX also show improved processibility and mechanical properties. In such materials the crystalline explosive is embedded in a rubber-like polymeric matrix. One of the most prominent examples of a PBX is Semtex. Semtex was invented in 1966 by Stanislav Brebera, a chemist who worked for VCHZ Synthesia in Semtin (hence the name Semtex), a suburb of Pardubice in the Czech Republic. Semtex consists of varying ratios of PETN and RDX. Usually polyisobutylene is used for the polymeric matrix, and phthalic acid n-octylester is the plasticizer. Other polymer matrices which have been introduced are polyurethane, polyvinyl alcohol, PTFE (teflon), Viton, Kel-F and various polyesters. [Pg.10]

When embedded in thin PET films at levels (10wt%) comparable to those achieved in cotton/polyester blend fabrics via bath padding and oven-curing 4-12 wt%), substantial flame retardancy is imparted to the PET films. This despite the fact that the molecular weights of FR and (i-CD are 401 and 1,135, respectively, which suggests that the FR is actually present at much reduced levels in the FR-P-CD-IC embedded PET films. [Pg.154]

True random orientation mounts are difficult to prepare, and numerous techniques for filling powder sample holders have been described (Brindley and Brown, 1980). For example, powder samples have been embedded in plastic (Brindley and Kurtossy, 1961), polyester foam (Thompson et al., 1972), mixed with powdered cork (Wilson, 1987), pasted in acetone prior to smearing onto glass slides (Paterson et al., 1986) and spray dried (Hillier, 2002). [Pg.431]

A schematic diagram of a typical commercial composite membrane is presented in Figure 1. The microporous polysulfone support film is cast on a woven or nonwoven backing material, usually made from polyester fibers. The polysulfone support is approximately 50 urn (two mils) in thickness. About half of this thickness sits above the polyester backing material, and about half of it is embedded in the fibrous carrier web. The thickness of the applied barrier layer may range from 20 to over 500 nm, depending upon the composition of the barrier layer. [Pg.273]

After biosynthesis of the polyester and separation of the bacterial biomass from the supernatant, the required recovery process (typically a solid-liquid extractiOTi procedure) can constitute another not negligible cost factor, especially in large-scale production. Here extraction solvents that can easily be recycled will be of interest [53]. In order not to leave the patterns of sustainability in biopolymer production, it will be indispensable to concentrate the development of new extraction processes on such recyclable solvents that are also of environmentally sound nature [54], Typical harmful chlorinated solvents like chloroform must be avoided. A PHB production process embedded in an ethanol production plant has the advantage to utilise the medium chain length alcohol fraction (fusel alcohols) from the distillery step, consisting mainly of iso-pentanol. The application of the fusel alcohols as extracting solvents unites two important points On the one hand, this liquid normally constitutes a surplus product that has little market value. When used as an extraction solvent the costs for alternative solvents are saved. Furthermore, this extraction solvent is less harmful to handle than the classical extraction solvent chloroform [27],... [Pg.89]

TPS-polyester) and the composite (TPS fibres), without synergetic effect between them. In fact, the fibres embedded in the polyester phase did not participate to the cellulose-TPS network (dilution effect). [Pg.259]

Embedded strain gages with 100mm of gage length, were Installed in polyester resin concrete when the specimens were molded. The length change was measured by static strain meter connected with a timer at 20°C, 50 % R.H. The measurements were conducted at Intervals of 5 minutes for 60 minutes after adding the catalyst to... [Pg.68]

These premises can be taken as the major reasons for the rationale that brought us to contribute to meetings, such as the first and the second Joint Polish-Italian Seminar, expressely devoted to "polymer blends". In this context, we present the results of the work done in part at the University of Pisa and in part at the University of Massachusetts in the field of the preparation and characterization of polyester systems containing p-oxybenzoate residues, as the anisotropic moieties, embedded in structurally ordered macro-molecular segments. Linking units in the hard segments are the terephthaloyl (Series I, IV, and V), oxalyl (Series II) and carbonyl... [Pg.267]

The ribs were manufactured from FRP composites. The laminate used glass fibres in tissue form and rovings as additional reinforcement, embedded in a matrix of unsaturated polyester (PU) resin. A gel coating provides protection. [Pg.444]

The pultruded GFRP profiles consisted of E-glass fibers embedded in an isophthalic polyester resin. The environmental exposition of the GFRP profiles corresponds to a typical alpine cHmate. The mean annual temperature is approximately 4°C with maximum values of approximately 25 °C in the summer and a minimum of—20° C in winter. The aruiual hours of sunshine are approximately 1700 and the average annual rainfall is 1000 mm. The alpine location exposes the white colored bridge to high UV radiation. A layer of dense snow normally covers the walkway [14]. [Pg.8]

The pultruded GFRP material investigated in [21] was produced by Fiberline Denmark and composed of E-glass fibers embedded in an isophthalic polyester resin (fiber weight fraction 57.6%). Two specimens were prepared as 100 mm square plates with 6 mm thickness. Only the through-thickness thermal conductivity was measured. The hot plate sensor was placed between the two plates and was then heated by an electrical current for a short period of time. The dissipated heat caused... [Pg.60]

Classification Thermoplastic elastomer Definition Polymer consistg. of hard segments embedded in a soft, elastomeric polyol phase exc. abrasion/impact resist. high str. wide working temp, range good hydrolytic stability two types polyether- or polyester-based Properties Solid... [Pg.3587]


See other pages where Embedding in polyesters is mentioned: [Pg.191]    [Pg.348]    [Pg.93]    [Pg.84]    [Pg.277]    [Pg.31]    [Pg.191]    [Pg.348]    [Pg.93]    [Pg.84]    [Pg.277]    [Pg.31]    [Pg.500]    [Pg.152]    [Pg.434]    [Pg.226]    [Pg.543]    [Pg.351]    [Pg.263]    [Pg.242]    [Pg.212]    [Pg.152]    [Pg.35]    [Pg.146]    [Pg.170]    [Pg.59]    [Pg.833]    [Pg.263]    [Pg.274]    [Pg.8]    [Pg.328]    [Pg.70]    [Pg.87]    [Pg.88]    [Pg.194]    [Pg.216]   
See also in sourсe #XX -- [ Pg.151 ]




SEARCH



© 2024 chempedia.info