Solid polyamide resins

Chemistry of Dimer-Based Polyamide Resins Solid Polyamide Resins Properties... 

Properties. The solid polyamide resins are alcohol soluble and if properly formulated can supply some degree of hydrocarbon compatibility. Thus, they can be applied from solvent solution. However, they also can be applied as hot melts or from water dispersions. Water-based forms known as suspensoids have been described (12). Solid polyamides also may be finely divided for use as powders. The films are characterized by resistance to moisture, moisture vapor transmission, grease, and oils. They are resistant to many solvents and chemicals including aliphatic hydrocarbons and mineral and vegetable oils. They do not resist lacquer-type solvents and alcohols. They have a high degree of flexibility and maintain their flexibility upon aging. Also, they are heat sealable at relatively low temperatures and adhere to an unusually wide variety of substrates. 

Because of this steep viscosity drop, solid polyamide resins are useful as hot melt adhesives. The resins may tend to "skin" or oxidize when exposed to air and high temperatures for long periods. However, this negative property can be circumvented by the use of antioxidants and by proper application equipment design. 

Fig. 5. Examples of ihe correlation between measured adhesive strength and (l+cos6). (a) Plot of data from Raraty and Tabor [171J for adhesion of ice to various solids, (b) Plot of data of Barbaris [172] for adhesion of a mixture of epoxy and polyamide resin to low density poly(ethylene) treated in various ways. Both figures from ref. [31], by permission.

Applications of cation and anion resins are varied and include purification of sugar, identification of drugs and biomacromolecules, concentration of uranium, calcium therapy to help increase the amount of calcium in our bones (i.e., increase the bone density), and use as therapeutic agents for the control of bile acid and gastric acidity. In the latter use, a solid polyamide (Colestid) is diluted and taken with orange juice, which facilitates removal of bile acids from the body. This removal helps the body to produce more bile acid from cholesterol, thus effectively reducing the cholesterol level. 

Ambient-cure systems are often based on lower molecular-weight solid epoxy resins cured with aliphatic polyamines or polyamides. Curing normally occurs at ambient temperatures with a working life (pot life) of 8—24 h, depending on the formulation. Epoxy—polyamine systems are typically used for maintenance coatings in oil refineries, petrochemical plants, and in many marine applications. Such coverings are applied by spray or brush. These are used widely where water immersion is encountered, particularly in marine applications (see COATINGS, MARINE). 

In 1971, Sheppard proposed that peptide synthesis would proceed more efficiently if the polymeric support was designed to have solvation properties similar to those of the peptide product.This line of reasoning led to the development of polyamide resins.The most successful of this type of support is based on cross-linked poly(dimethylacrylamide) (Pep-syn). Polyamide resins swell up to 10 times their dry volume in dimethylformamide and even more in water. On the other hand, they swell much less in dichloromethane. The few comparative studies that have been carried out between polystyrene and polyamide resins indicate that both give very similar results in routine solid-phase peptide synthesis. 

Coatings. The solid dimer polyamide resins are useful as protective coatings and inks on many substrates, especially flexibile ones like polyolefin film, paper, fiberboard, and metal foils. Thus, paper converters use these resins by applying them from solvent by roller-... 

The reactive dimer polyamides and fatty amido amines are liquid resins with many of the properties described above for solid polyamides. In addition, they are amine-like in that they are basic and form salts. They are more soluble than solid resins, although alcohols are still primary solvents. 

The solid support should be well solvated to facilitate reactions to take place involving the two phases. The original supports were based on polystyrene but have generally been superseded by polyamide resins, which have an advantage in that they have a similar polarity to the peptide backbone. More recently, resins based on polyethylene glycol (PEG) grafted onto low... 

Uses Surfactant for industrial applies., lubricants in prod, ot solid and liq. reactive polyamide resin compositions for crosslinking polyesters to enhance toughness and flexibility defoamer in food-contact coatings, paper/paperboard food pkg. adhesives, coatings, paper, cellophane, polymers... 

Chem. Descrip. o,p-Toluenesulfonamide-formaldehyde resin CAS 1338-51-8 EINECS/ELINCS 215-667-5 Uses Modifier and adhesion promoter for syn. and natural resins used in adhesives and coatings applies. extender in polyamide resins food pkg. adhesives, paper, cellophane Reguiatory FDA 21CFR 175.105,176.170,177.1200 Properties Pract. colorless hard solid particles, faint formaldehyde odor sol. in usual lacquer soivs. Insol. In water, aliphatic hydrocarbons, veg. oils sp.gr. 1.35 soften, pt. 62 C ref. index 1.4275-1.4325 (25 g/75 g butyl acetate)... 

Chem. Deschp. Polyamide in propylene glycol methyl etherAtylene sol n. Uses Epoxy curing agent in solvent-based maintenance coatings Features Used with solid epoxy resins offers fast cure, good chem. resist. 

Paints, varnishes and lacquers based on epoxy resins are used in various industrial applications because of their strength and durability. Two-component epoxy paints that cure at room temperature need a hardener added before their use. One-component epoxy paints that are heat-cured contain a hardener which can be activated only by heating. Polyfunctional aliphatic amines, aromatic amines, solid polyamides and anhydrides can be used as curing agents. Epoxy-ester-resin paints are formed by reacting epoxy resin with... 

These resins were somewhat brittle. They bonded well to porous substrates but found limited application unless modified by compounding in order to improve flexibility and adhesion to nonporous surfaces. For example, blending of solid thermoplastic resins with the reactive polyamides resulted in hot melt adhesives which bonded well to metals and other substrates, and also had improved flexibility. 

Effluents from the manufacture of Pb(C2H5)4 can be treated with a macromolecular sulfonate-type strongly acidic cation exchange resin [572], tuff [738], chlorine [678, 691, 693], or ozone [678, 691, 704]. Extraction has also been used for removal of Pb(C2H5)4 from waste water [678, 691 to 693]. In addition, contact with a solid polyamide absorbent such as nylon or nylon 6 is patented [721]. The efficiency of various methods is compared [691]. A submarine dispersal system has been described [416]. 

A large variety of different materials have been tried as insoluble supports during the evolution of oligonucleotide synthesis, and the major materials are described in Table 1. The first solid-phase oligonucleotide syntheses were performed using the same nonpolar popcorn polystyrene resin (3,4) used for peptide synthesis (Fig. 5). Later, polar polyamide resins were developed that were more suitable for the polar solvents used in early phosphodiester (5)/triester (d) methods (Fig. 5). 

The investigation of minor groove-binding polyamides was greatly accelerated by the implementation of solid-phase synthesis [48]. Originally demonstrated on Boc-y9-Ala-PAM resin with Boc-protected monomers, it was also shown that Fmoc chemistry could be employed with suitably protected monomers and Fmoc-y9-Ala-Wang resin (Fig. 3.8) [49]. Recently, Pessi and coworkers used a sulfonamide-based safety-catch resin to prepare derivatives of hairpin polyamides [50]. Upon activation of the linker, resin-bound polyamides were readily cleaved with stoichiometric quantities of nucleophile to provide thioesters or peptide conjugates. 

Fig. 3.8 Variations to solid phase synthesis of polyamides. Use of Fmoc monomers on jS-Ala-Wang resin (left) provides polyamides containing a jS-alanine residue near the C-ter-mini. Polyamides synthesized on the Kaiser...

Belitsky, J.M., D. H. Nguyen, N. R. WuRTZ, and P. B. Dervan. Solid-phase synthesis of DNA binding polyamides on oxime resin. Bioorg. Med. Chem. 2002,... 

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