Polypropylene resins monomer

In this later study, excellent separation was achieved probably due to the fact that their column separation technique included the crystallization of the polypropylene resins onto the sand column packing by slow cooling. Since the copolymers were made using -- enriched monomer, C-NMR analysis on... 

Significant progress in this area has been made. It has been shown recently that the polarity of the casting substrate may provide an avenue for surface wetting without surface treatment. The casting of silicone-based formulations from polar mold materials results in a surface rich character. For example, a copolymer based on a fiuorinated silicone and the hydrophilic monomer, DMA was cast against the hydrophilic mold resin Barex (copolymer of acrylonitrile and styrene). X-ray photoelectron spectroscopy analysis of the surface showed a threefold increase in surface nitrogen concentration as compared with the same formulation cast from a hydrophobic polypropylene resin. The Barex cast material resulted in... 

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... 

Polypropylene Plastic or resin derived from the polymerization of propylene as the principal monomer. 

In 1955, Pruitt and Baggett (4,5) reported the polymerization of propylene oxide catalyzed by the reaction product of ferric chloride and propylene oxide, i.e., Pruitt-Baggett catalyst . Polypropylene oxide obtained from DL-monomer could be fractionated into two parts, one rubbery and another resinous. The latter fraction gave a discrete crystalline X-ray diffraction pattern. 

Polymers are large molecules (macromolecules) that consist of one or two small molecules (monomers) joined to each other in long, often highly branched, chains in a process called polymerization. Both natural and synthetic polymers exist. Some examples of natural polymers are starch, cellulose, chitin (the material of which shells are made), nucleic acids, and proteins. Synthetic polymers, the subject of this chapter, include polyethylene, polypropylene, polystyrene, polyesters, polycarbonates, and polyurethanes. In their raw, unprocessed form, synthetic polymers are sometimes referred to as resins. Polymers are formed in two general ways by addition or by condensation. 

The 50% aqueous acrylamide is the preferred form because it eliminates the handling of solids and because its cost is lower. This is a result of the new manufacturing method put into effect in 1971. The aqueous form is applicable to nearly all the end uses of acrylamide when volume is taken into account. Aqueous acrylamide is shipped in tank trucks, rail cars, or dmms, but small samples can also be obtained. The solution should be kept in stainless steel or in tanks coated with plastic resin (phenolic, epoxy, or polypropylene). All containers, including tank trucks and rail cars, must be rinsed prior to disposal or return. When shipping costs are an important consideration, solid acrylamide may be the desired form. Acrylamide should be stored in a well ventilated area away from sunlight. The temperature should be under 30°C, and under these conditions no change of quality should be noticed for at least 3 months. Typical specifications for the 50% aqueous solution are shown in Table 5 and for the solid monomer in Table 6. 

Furthermore, monomers from which crystalline homopolymer can be produced, such as high-density polyethylene and polypropylene, can be copolymerized to produce resins with controllably reduced crystallinity and thus greater transparency. The ethylene/propylene copolymers may range from partially crystalline plastics to amorphous elastomers. 

---