Synthetic resins: I. Preparation and characterization of resins from substituted benzoic acid–formaldehyde

A number of resins have been prepared by the condensation of substituted benzoic acid with formaldehyde in the presence of different acids and bases as the catalyst. The intrinsic viscosity and Huggin's and Kraemer's constants of the resins were determined. The solubility behavior of the resins was studied. The IR spectra and the thermogravimetric analysis of the resins were also studied. The values of the energy of activation of degradation of the resins were computed by using the Freeman–Anderson method.     

Synthetic resins,IV. Preparation and characterization of resins prepared from hydroxyacetophenone

New resins have been synthesized from o-hydroxyacetophenone by reaction with substituted aromatic compounds and formaldehyde in the presence of various acids and bases as catalyst following two different techniques. The polymer samples are characterized by IR spectra. The solution, thermal, and chemical properties of the resins are investigated. The solubility parameters of the resins calculated according to the investigations of Small agree well with the experimental values. The resins are found to be fairly thermostable and the energy of activation is evaluated from TG curve by applying (i) Freeman-Anderson method and (ii) Broido method.     

Synthetic resins. XIII. Synthesis and characterization of the resins derived from quinacetophenone/substituted benzoic acid/furfuraldehyde

Some resins have been synthesized by reacting quinacetophenone with substituted benzoic acids and furfuraldehyde in the presence of basic catalysts. The resins have been characterized by IR spectra of the characteristic groups. The number average molecular weights of the resins have been evaluated by the conductance method. The solubility and viscosity behaviors of the resin copolymers have been determined. Cu⁺², Ni⁺², Co⁺², Mn⁺², and Mg⁺² chelates have been prepared. The resins were shown to be selective ion-exchange resins for certain metal ions. A batch equilibrium method was used for studying the selectivity of the metal ions. The thermal behavior of the resins has been determined and the values of energy of activation of the resins were computed by using the Freeman–Anderson and Broido methods. The biological assays of some of the resin copolymers were found to be highly sensitive.     

Synthetic resins. XX. Chelation ion exchange properties of resins derived from semicarbazone of 2-hydroxy acetophenone-substituted benzoic acid–formaldehyde

A number of resins have been synthesized by reacting orthohydroxy acetophenone-semicarbazone with substituted benzoic acid and formaldehyde in the presence of some acid and basic catalyst. The physicochemical properties of the resins have been reported. The ion exchange properties of the resins have been investigated. Influence of electrolytes on the metal uptake of Cu²⁺, Ni²⁺, Zn²⁺, Mg²⁺, and Mn²⁺ has been studied. The distribution of metal ions at different pH has also been reported. © 1992 John Wiley & Sons, Inc.     

Synthetic resin. XI. Preparation and characterization of resins derived from picoline and lutidine/aromatic hydroxy,amino, and chloro compounds/formaldehyde

A number of resin copolymers have been prepared by condensing α-picoline, γ-picoline, and lutidine separately with hydroxy acetophenone, hydroxy, amino, chloro benzoic acids, and toluic acid in the presence of sodium hydroxide and succinic acid as catalyst. The resins were characterized by infrared spectra of the characteristic groups. The solubility parameters were calculated from Small's group's contribution. The antifungal activity of the resins have also been investigated.     

Preparation and adsorption properties of chelating resins from thiosemicarbazide and formaldehyde

A novel chelating resin was synthesized in just one step under mild synthetic conditions. The synthesis was carried out through the copolymerization of thiosemicarbazide and formaldehyde in an aqueous solution. The adsorption properties for some noble metal ions were investigated. The results showed that the resin had high adsorption selectivity for Au(III) and Ag(I). The adsorption capacities for the two metal ions reached up to 7.3 and 11.8 mmol/g, respectively. The adsorption rate for the two metal ions in a dilute solution was 99.9%. The adsorption fit first‐order kinetics, and an isothermal adsorption study indicated that it corresponded to Langmuir monomolecular layer adsorption. The change in the bonding energy during the chelating process was investigated with X‐ray photoelectron spectroscopy. The study revealed that nitrogen and sulfur atoms of the resins were electron donors and metal ions were electron acceptors in the process. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Synthetic resins. XVIII. Chelation ion exchange properties of 2,4-dinitrophenylhydrazone of 4-hydroxy acetophenone–formaldehyde resins

A large number of copolymers were synthesized by condensing 2,4-dinitrophenyl hydrazone of 4-hydroxy acetophenone (4HA 2,4 DNPH) with substituted benzoic acids/phenols and formaldehyde in the presence of NaOH or HCl as catalyst. The resins were characterized by IR spectra. The decomposition temperature, solubility parameter, and viscositv of the polymers have been determined. The ion-exchange properties have been studied using the batch equilibrium method. The measurement of the distribution of a given metal ion between an aqueous solution and the resins has been performed. The investigation was carried out over a wide range of pH and varying the ionic strength of the medium. © 1992 John Wiley & Sons, Inc.     

Chemical modification of polystyrene. V. Sulfonic acid resins from anhydride substituted polystyrene

Chemically modified polystyrenes based on the condensation of polystyrene with phthalic anhydride, trimellitic anhydride, and cis-1,2,3,6-tetrahydrophthalic anhydride have been processed into sulfonic acid cation exchange resins. The effects of variation of sulfuric acid amount and the temperature of sulfonation on the synthesis and the ion-exchange capacities of the resins have been established. The resins have finally been characterized with respect to their structures by IR and elemental analysis data. The total ion exchange capacity as well as the salt-splitting capacity and the pH-metric titration characteristics of these resins have also been determined. These resins posses better ion-exchange capacities than the conventional styrene based resins.     

Synthesis and properties of cationic resins derived from aniline/benzylamine-modified epoxy resins and diethylamines

Aniline/benzylamine-modified epoxy resins with different molecular weights, which contain tertiary amines in the middle of the polymer chain, were synthesized by the reaction of aniline/benzylamine with epoxy resin at various molar ratios. The resulting aniline/benzylamine-modified epoxy resins were reacted with diethylamine and subsequently reacted with 2-ethylhexanol-blocked toluene diisocyanate to obtain thermally crosslinkable resins which contain tertiary amines at the end and in the middle of the polymer chain. These resins were partially neutralixed with acetic acid to give thermally crosslinkable cationic resins. The resulting cationic resins were dissolved in suitable solvents and mixed with deionized water to form various emulsions. The emulsion and electrodeposition properties of these resins were studied in some detail to compare the properties of these cationic resins. The results show that the deposition yields and throwing power of the emulsions prepared from benzylaminemodified epoxy resins are higher than those of the emulsions prepared from anilinemodified epoxy resins. The emulsion having proper pH values can give a high throwing power. High throwing power is the characteristic property of these modified cationic resins. Factors determining the throwing power and deposition yield of the emulsions were also investigated.     

Preparation and adsorption properties of resins containing amine,sulfonic acid,and carboxylic acid moieties

Completely water‐insoluble resins containing amine, carboxylic acid, and sulfonic acid as ligand groups were synthesized by radical polymerization in solution. The yield was higher than 97%. The resins were characterized by FTIR spectroscopy and thermal analysis. The metal ion retention properties at different pH values were investigated by a batch method. Metal ions studied were: Cu(II), Cd(II), Zn(II), Hg(II), Pb(II), and Cr(III). The metal ion binding ability depended strongly on the pH. The retention properties were also tested under competitive conditions. Elution of the metal ion was investigated in acid medium at different concentrations. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 700–705, 2003     

Preparations and properties of phenanthrene - formaldehyde resins

Phenanthrene was treated with formaldehyde in the presence of sulphuric acid and the yields of resin obtained were dependent on the acid concentration and on the molar ration of formaldehyde to phenanthrene. All of the resins were composed of dimers, trimers, tetramers and higher oligomers. The bridges joining the phenanthryl units were mainly methylene when formaldehyde was in molar deficit relative to phenathrene, but dimethylene ether and acetal bridges were present when the formaldehyde was in molar excess.     

Preparation of cured urea–formaldehyde resins of low formaldehyde emission

Several polymers containing amino or amido groups and biuret were tested as additives to ureaformaldehyde (UF) resin in order to neutralize its inherent acidity and combine free formaldehyde released upon hydrolysis of cured UF polycondensate. Each modifier was incorporated to liquid methylolureas at weight ratios of 1:100, 2:100, and 3:100 prior to curing with the aid of acetic acid. Over 10 days of maintaining aqueous suspensions of the ground-up resultant solid resins at ambient temperature, a neutralizing effect was exhibited most visibly by polyacrylamide, polymethacrylamide, and biuret, the test with chitosan and casein giving results slightly different from those obtained for the control nonmodified cured UF polymer. Polyacrylamide, biuret, and casein proved to be excellent inhibitors of formaldehyde release from the hardened resins which were suspended in water at ambient temperature. On the other hand, chitosan did not reduce the evolution of HCHO but, instead, augmented it when its content was 1 g/100 g of the original liquid resin before cure.     

Wholly aromatic polyamide-hydrazides. V. Preparation and properties of semipermeable membranes from poly[4-(terephthaloylamino) benzoic acid hydrazide]

Effects of several processing parameters on the properties of poly[4- (terephthaloylamino) benzoic acid hydrazide] semipermeable membranes were investigated. The membranes were prepared using a polymer phase inversion method that consisted of the following sequence of steps: casting of thin, neutralized polymer solution layers on suitable solid support; thermal treatment of the obtained layers to form viscous liquid protomembranes; coagulation of the protomembranes into solid semipermeable membranes; and, when that was additionally desired, posttreatment of the obtained membranes in order to further affect their final separation properties. The processing parameters investigated included temperature and time of exposure to thermal treatment during the preparation of protomembranes, nature of the employed medium, time of exposure, and temperature of the posttreatment of coagulated membranes. In addition, particular attention was devoted to the effect of polymer molecular weight on the properties of the membranes, and for that purpose a series of five polymer samples with molecular weights that ranged from about 17,000 to about 64,500 was prepared using the previously described viscometrical method to monitor the polymer forming polycondensation reactions. The results obtained showed that membrane performance was very much influenced by all of the examined processing variables and that products with considerably different properties could be obtained from the same polymer sample by using different processing parameters. Thus, the use of higher temperatures and longer exposure times in the protomembrane forming thermal treatment step gave higher rejection and lower permeability of the finished membranes, although there seems to exist limiting “ceiling conditions” above which this trend rather abruptly ceases to continue any further. It appears that these conditions correspond to the onset of irreversible changes, either in the polymer chemical structure or in the membrane supermolecular organization. Posttreatment of the prepared membranes was found essential for useful properties in the single-stage separation applications, which require high membrane selectivity. Of the investigated possibilities, annealing in boiling deionized water was crucial, while exposure to concentrated acids was also important in the case of HCl but rather deleterious in the case of H₂SO₄. Most significantly, the membrane properties clearly depended on the polymer molecular weight, and it was found that there was a critical polymer molecular weight above which this dependence ceased to be important for practical purposes. It is suggested that this may be a general phenomenon, characteristic for all membrane forming polymer materials, and a possible explanation of its nature is tentatively offered.     

Preparation and properties of epoxy/phenol formaldehyde novolac/hexakis(methoxymethyl)melamine hybrid resins from in situ polymerization

Based on the self‐condensation of hexakis(methoxymethyl)melamine (HMMM), the condensation between HMMM and phenol formaldehyde novolac resin (n‐PF), and the addition reaction of diglycidyl ether of biphenyl A (DGEBA) and n‐PF, a homogeneous, transparent hybrid thermoset was prepared via in situ polymerization of DGEBA, n‐PF, and HMMM. No phase separations were observed even for the DGEBA/n‐PF/HMMM hybrid thermoset containing 40 wt % HMMM. These hybrid thermosets had high glass‐transition temperatures (98–127°C from differential scanning calorimetry and 111–138°C from dynamic mechanical analysis), excellent thermal stability with high 5 wt % decomposition temperatures (>322°C), high char yields (>24 wt %), and improved flame retardancy with high limited oxygen indices (>28.5). The excellent overall properties of these hybrid resins may lead to their applications in high‐performance “green” electronic products. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Chelation ion‐exchange properties of copolymer resin derived from 4‐hydroxyacetophenone,oxamide, and formaldehyde

A copolymer (4‐HAOF) prepared by condensation of 4‐hydroxyacetophenone and oxamide with formaldehyde in the presence of an acid catalyst proved to be a selective chelating ion‐exchange copolymer for certain metals. Chelating ion‐exchange properties of this copolymer were studied for Fe³⁺, Cu²⁺, Ni²⁺, Co²⁺, Zn²⁺, Cd²⁺, Pb²⁺, and Hg²⁺ ions. A batch equilibrium method was employed in the study of the selectivity of metal‐ion uptake involving the measurements of the distribution of a given metal ion between the copolymer sample and a solution containing the metal ion. The study was carried out over a wide pH range and in media of various ionic strengths. The copolymer showed a higher selectivity for Fe³⁺ ions than for Co²⁺, Zn²⁺, Cd²⁺, Pb²⁺, Cu²⁺, Ni²⁺, and Hg²⁺ ions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 787–790, 2003     

Lubricants. I. Preparation and properties of benzyl and substituted benzyl esters of dilinoleic acid

Benzyl and substituted benzyl esters of dilinoleic acid and of hydrogenated dilinoleic acid have been prepared in good yield. Some of the chemical characteristics and physical properties of the resulting products have been measured including a study of their thermal stability by thermogravimetry. Also, they have been examined by several of the bench tests used in laboratory evaluation of lubricants. Several of them compare favorably with control materials used in the study. E. Utiliz. Res. Devel. Div., ARS, USDA.