Polymer resin polypropylene

Aqueous solutions of 50% acrylamide should be kept between 15.5 and 38°C with a maximum of 49°C. Below 14.5°C acrylamide crystallizes from solution and separates from the inhibitor. Above 50°C the rate of polymer buildup becomes significant. Suitable materials of constmction for containers include stainless steel (304 and 316) and steel lined with plastic resin (polypropylene, phenoHc, or epoxy). Avoid contact with copper, aluminum, their alloys, or ordinary iron and steel. 

Relatively small changes in comonomer content can result in significant changes in physical or chemical properties. Polymer resin manufacturers exploit such relationships to control the properties of their products. The composition of a copolymer controls properties such as stiffness, heat distortion temperature, printability, and solvent resistance. For example, polypropylene homopolymer is brittle at temperatures below approximately 0 °C however, when a few percent ethylene is incorporated into the polymer backbone, the embrittlement temperature of the resulting copolymer is reduced by 20 °C or more. 

Polymer chemistry is important in obtaining adhesion to the glass surface (Figure 10). The tensile reinforcement factor—the ratio of tensile strengths of the reinforced system to the matrix resin—is used as a measure of adhesion. Two dissimilar polymers, polypropylene and nylon, are used to illustrate the importance of polymer chemistry. Polypropylene is an inherently difficult polymer to reinforce because of its nonpolar nature and lack of reactivity. Nylon, on the other hand, is highly polar and is one of the easiest thermoplastics to reinforce. The modified poly-... 

This review summarizes our work at the University of Bayreuth over the last few years on improving the electret performance of the commodity polymer isotactic polypropylene (Sect. 3) and the commodity polymer blend system polystyrene/polyphenylene ether (Sect. 4) to provide electret materials based on inexpensive and easily processable polymers. To open up polymer materials for electret applications at elevated temperatures we concentrated our research on commercially available high performance thermoplastic polyetherimide resins and synthesized several fluorinaled polyetherimides to identify structure-property relations and to improve further the performance at elevated temperatures (Sect. 5). 

Plastics and rubber are essential materials in today s industrialized societies. The consumption of plastics has grown by a factor of about 60 in the past 30 years, which has led to a corresponding increase in the generation of plastic wastes. One of the most valuable properties of plastics, their low density, is one of the major limitations in the recycling of plastic wastes. Thus, to recover one tonne of plastics it is necessary to collect about 20 000 plastic bottles. Plastic wastes are mainly found in municipal solid wastes (MSW). As a consequence of their low density, plastics account for just 8 wt% of the MSW, but this value increases to over 20% in volume terms. In spite of the great diversity of plastic materials, plastic wastes are made up of a relatively small number of polymers polyethylene, polypropylene, polystyrene, polyvinyl chloride and polyethylene terephthalate. These resins account for more than 90% of total plastic wastes. 

U.S. Pat. No. 6,590,004 [121] (by Crane Plastics Company, TimbeiTech) discloses a foamed fiber composite comprising 40-80% by weight of PVC or polypropylene, 20-60% by weight of cellulosic fiber, and additives such as stabilizer(s) in an amount of 1-10% per the polymer resin, lubricant(s) in an amount of 1-12% per the polymer resin, process aid(s) in an amount of 0.25-5% per the polymer resin. 

Sumilizer BBM-S SWP SWP (antioxidant) Yoshinox BB, Antioxidant for polypropylene, polyethylene, nylon molding powders, and other polymer resins. DuPont Great Lakes Fine Chem. Monsanto Co. 

Experimental plan. Table 1 presents the experimental plan of this study. High-strength concrete with 25% W/B and incorporating 20% fly ash (FA) and 10% silica fume (SF) was fabricated. A number of trial mixes were performed to secure 700 mm slump flow and 3. 0% air content. For the polymer resin, ethylene vinyl acetate copolymer (EVA-P) and polyvinyl acetate copolymer (PVA-P) powders and PVA (PVA-F) and polypropylene (PP-F) fibers were applied. The dosages ranged from 0.1% to 0.5% for powder-type resins and from 0.05% to 0.15% for fiber-type polymers. 

The word polymer is the odd one. It simply means a substance composed of very large molecules, which in turn are built up repetitively from small chemical building blocks called monomers or mers . Examples of polymers are polypropylene, nylons (properly called polyamides), epoxy resins, polyimides, etc. 

Potentially, this direct fluorination process is a new approach to the synthesis of fluorocarbon polymers. Polyethylene, polypropylene, polystyrene, polyacrylonitrile, polyacrylamide, resor phenol formaldehyde resin, and ethylene propylene copolymer have been fluorinated to produce perf1uorocarbon polymers which are structurally similar to the hydrocarbon starting materials and have physical properties similar to known structurally related fluorocarbon polymers obtained by polymerization of fluorocarbon monomers. High yield of fluorocarbon polymers approaching 100 have been obtained. This direct technique used for fluorination of hydrocarbons and polymers is called the LaMar process and has been previously described in connection with the direct fluorination of Lt ver molecular weight species ". ... 

Packaging constitutes the single largest end use for plastic materials, primarily the commodity resins polypropylene (PP), polyethylene (PE), polystyrene (PS), polyvinyl chloride (PVC), and polyethylene terephthalate (PET). Nylons (PA) are an important exception, because film for food packaging is a major market for these polymers. 

In summary, therefore, continued investment in the understanding of ziegler-Natta catalysis has developed an ideal catalyst for polyolefins. Polypropylene now stands at a crossroads with many more new opportunities possible. The production of the final polymer resin in the reactor without the need for subsequent remelting and pelletizing has expanded the potential for modifying this most versatile polymer to develop unique combinations of properties that enable it to compete economically with a wide range of existing... 

Iron oxide nanocomposites have been prepared by hydrolysis of iron salts in sulfonated polystyrene resins, mesoporous sulfonated styrene-divinylbenzene copolymer, acrylonitrile-methyl methaciylate-divinylbenzene copolymer, cross-linked high amylose starch, polyimides, polyvinylpyridine, polypyrrole,eellulosies. Nanocomposites of metals (Cr, Mo, W, Fe, Co, Ni) with a variable particle size (2-10 mn), have been prepared from solutions of metal preeursors in a molten polymer (polyethylene, polypropylene, polytetra-fluoroethylene, polyamide, polyaiylate, polycarbonate, polystyrene, polyethers, polyphenyleneoxide, siloxane). There are also many examples of in-situ precipitation of iron oxides in aqueous solution of polymers, such as dextran, PVA, polyethylene glycol, etc. In this case, size dispersion and aggregation are frequent, but they can be minimized by using reverse micelles. ... 

Formulation-designed hot melt adhesives use a number of materials as the base polymer for the formulation. The most widely used material for this type of adhesive is polyethylene-co-vinyl acetate (EVA). Other materials used are polyethylene (low density), block copolymers (styrene-iso-prene-styrene), phenoxy resins, polypropylene, and paraffin waxes. Paraffin, the oldest hot melt adhesive, was used as a sealing wax. As with PSAs, tackifiers are also added to hot melt adhesives to lower their melt viscosity as well as to provide tack during the resolidification of the adhesive. If one examines some hot melt adhesive formulations, one finds that the tackifier is a primary component of the adhesive sometimes used to the same level or possibly in excess of the hase polymer. Another component is the addition of a wax. The wax is added not only to decrease the melt viscosity of the adhesive but also to aid in the recrystallization process. As one might be able to recount from statements made above about heat stability, an antioxidant is an important additive to hot melt adhesive formulations. Final additives indude colorants and fillers. 

This type of adhesive is generally useful in the temperature range where the material is either leathery or mbbery, ie, between the glass-transition temperature and the melt temperature. Hot-melt adhesives are based on thermoplastic polymers that may be compounded or uncompounded ethylene—vinyl acetate copolymers, paraffin waxes, polypropylene, phenoxy resins, styrene—butadiene copolymers, ethylene—ethyl acrylate copolymers, and low, and low density polypropylene are used in the compounded state polyesters, polyamides, and polyurethanes are used in the mosdy uncompounded state. 

In extmsion coating a polymer is extmded from a slot die into the nip of two roUs where it is bonded to a substrate under pressure (Fig. 6). A corona discharge may be appUed to the substrate just prior to the nip to enhance adhesion. Polyethylene or ionomer are the most common resins used in extmsion coatings. They provide improved moisture barrier (on paper), or sealabUity (on foU, polypropylene, or polyester). When a second substrate is introduced to the nip, laminated stmctures may be produced. 

Extmsion of polyethylene and some polypropylenes is usually through a circular die into a tubular form, which is cut and collapsed into flat film. Extmsion through a linear slot onto chilled rollers is called casting and is often used for polypropylene, polyester, and other resins. Cast, as well as some blown, films may be further heated and stretched in the machine or in transverse directions to orient the polymer within the film and improve physical properties such as tensile strength, stiffness, and low temperature resistance. 

Petroleum resins are low molecular weight thermoplastic hydrocarbon resins synthesized from steam cracked petroleum distillates. These resins are differentiated from higher molecular weight polymers such as polyethylene and polypropylene, which are produced from essentially pure monomers. Petroleum resin feedstocks are composed of various reactive and nonreactive aliphatic and aromatic components. The resins are usually classified as C-5... 

Other Uses. Large quantities of hydrocarbon resins are used in mastics, caulks, and sealants (qv). Polymers for these adhesive products include neoprene, butyl mbber, polyisoprene, NR, SBR, polyisobutylene, acryHcs, polyesters, polyamides, amorphous polypropylene, and block copolymers. These adhesives may be solvent or water-borne and usually contain inorganic fillers. 

Inversion ofMon cjueous Polymers. Many polymers such as polyurethanes, polyesters, polypropylene, epoxy resins (qv), and siHcones that cannot be made via emulsion polymerization are converted into latices. Such polymers are dissolved in solvent and inverted via emulsification, foUowed by solvent stripping (80). SoHd polymers are milled with long-chain fatty acids and diluted in weak alkaH solutions until dispersion occurs (81). Such latices usually have lower polymer concentrations after the solvent has been removed. For commercial uses the latex soHds are increased by techniques such as creaming. 

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