Sanjay V. Patel

Bioactive polymers: Synthesis, release study and antimicrobial properties of polymer bound Ampicillin

Matrices of poly(styrene-co-maleic anhydride) with surface containing functional anhydride groups of different percentage was prepared by solution polymerization. Ampicillin was bound on the surface of this matrix by chemical bonding in organic medium. The amount of Ampicillin chemically bound to the matrix was spectroscopically characterized and the in vitro release rate of Ampicillin in weakly basic medium was established along with the determination of its antimicrobial activity. This prodrug allows a prolonged release (6–8 days) of the drug. Mittels Losungspolymerisation wurden Poly(styrol-co-maleinsaureanhydrid)-Matrices mit unterschiedlichen Gehalten an oberflachenfunktionellen Gruppen hergestellt, an die dann Ampicillin chemisch gebunden wurde. Die gebundene Menge Ampicillin wurde spektroskopisch bestimmt. Die Geschwindigkeit der in-vitro-Freisetzung von Ampicillin in schwach basischem Medium und die antimikrobielle Aktivitat wurden ermittelt. Die Freisetzung des Medikaments last sich so bis auf 6–8 Tage verlangern.

Study on novel epoxy based poly(schiff reagent)s

Abstract Novel poly(schiff reagent)s from diketo derivative of epoxy resin were synthesised and characterised. A series of epoxy resin based poly(schiff reagent)s were synthesised by reacting an epoxy resin, diglycidyl ether of bisphenol-A (DGEBA) with 4-amino acetophenone (4-AAP) in a 1:2 mole ratio to afford the corresponding diketo derivative, and subsequent reaction with various aliphatic diamines in a presence of a triethyl amino as a catalyst. The resultant poly(schiff reagent)s were characterised by infrared spectroscopy (IR) and number average molecular weight (Mn) of PSs were estimated by non-aqueous conductometric titration. As produced, PSs having amine groups may act for curing of epoxy resins. Differential scanning calorimetric (DSC) curing kinetics of the epoxy resins viz. diglycidyl ether of bisphenol-A(DGEBA) and triglytidyl-p-amino phenol (TGPAP) have been investigated using PSs as a curing agent and triethyl amine as a catalyst. Thermal stability of the cured epoxy systems were studied by thermogravimetric analysis (TGA). The glass fiber reinforced composites of the produced PSs-epoxy system have been fabricated and were characterised by their mechanical properties and chemical resistance.

Novel vinyl ester resin and its urethane derivatives for glass reinforced composites

The paper describes glass-fibre-reinforced composites of a vinyl ester resin derived from triglycidyl-m-aminophenol and its urethane derivatives. The fabricated laminates were characterized by their mechanical properties and chemical resistance. The incorporation of vinyl monomer styrene in the resin system was found to improve some properties of composites remarkably. Aus Triglycidyl-m-aminophenol wurde ein neues Vinylester-Harz hergestellt und mit Diisocyanaten zu Urethanen derivatisiert. Aus diesen Harzen hergestellte glasfaserverstarkte Komposite wurden hinsichtlich ihrer mechanischen Eigenschaften und Chemikalienbestandigkeit untersucht. Durch Polymerisation in Gegenwart von Styrol werden die Eigenschaften merklich verbessert.

Epoxy resins-polyamide coating system

Abstract Bisester namely 1,1′-(1-methyl ethylidene) bis[4-{1-(1-imino-4-ethyl benzoate)-2-propa-nolyloxy}] benzene was synthesized by the reaction of epoxy resin (DGEBA) and 4-aminoethyl benzoate (4-AEB) using triethyl amine as catalyst. The synthesized bisester was reacted with three different aliphatic diamines viz; diethylene triamine (DETA), triethylene tetramine (TETA) and polyethylene amine (PEA) to obtained respective poly-amide resins (PAs) abbreviated as DGEBA-4-AEB: DETA, DGEBA-4-AEB: TETA and DGEBA-4-AEB : PEA respectively. The PAs synthesized were used as a curing agent for the difunctional epoxy resin (DGEBA) and trifunctional epoxy resin (TGPAP) in three different ratios. Using triethyl amine as a catalyst and PAs as a curing agent, DGEBA and TGPAP were polymerized on mild steel panels at 120[ddot]C for 1 hr. The coated panel thus obtained were tested for scratch hardness, flexibility, impact strength and chemical resistancy. It appears from the results for the epoxy resins, epoxy based poly...

Study on Novel Polyamides Based on Ester Terminated Epoxy Resin

The bisester 1, 1′-(1-methylethylidene)bis[4-{1-imino-4-ethylbenzoate-2-propanolyloxy}]benzene (DGEBA-4-AEB), synthesized by the reaction of the epoxy resin diglycidyl ether of bisphenol-A (DGEBA) with 4-amino ethyl benzoate (4-AEB), was condensed with different aromatic diamines, namely 4, 4′-diamino diphenyl methane (DDM), 4, 4′-diamino diphenyl sulfone (DDS) and benzidine (Ben) to yield novel epoxy based curing agents. The resultant novel epoxy based polyamides (PAs) were characterized by infrared spectroscopy along with the estimation of number average molecular weight (Mn ) by gel permeation chromatography (GPC). Using differential scanning calorimetry (DSC), the kinetics of the curing reactions of PAs–epoxy resin systems were established by evaluating the usual kinetic parameters. The thermal behaviour of PAs–epoxy cured products was also studied by thermogravimetric analysis (TGA).

Coating Properties of Di- and Tri-functional Epoxy Resin Using Novel Epoxy Based Polyamide as Curing Agent

Abstract Bis ester namely 1, 1′-(1-methylethylidene) bis[4-{1-(1-imino-4-ethyl benzoate)-2-pro-panolyloxy}]benzene was synthesized by the reaction of epoxy resin, diglycidyl ether of bisphenol-A-(DGEBA) and 4-amino ethyl benzoate (4-AEB) using triethyl amine as catalyst. The synthesized bisester was reacted with two different aliphatic diamines viz., 1. 4-butylene diamine (BDA) and 1. 6-hexamethylene diamine (HMDA) to obtain respective polyamide resins (PAs) abbreviated as DGEBA-4-AEB:BDA and DGEBA-4AEB:HMDA respectively. The PAs synthesized were used as a curing agent for the difunctional epoxy resin, (DGEBA) and trifunctional epoxy resin, (TGPAP) in three different ratios. Using triethylamine as a catalyst and PAs as a curing agent. DGEBA and TGPAP were polymerized on mild steel panels at 120°C for 1 hr. The coated panels thus obtained were tested for scratch hardness, flexibility, impact strength and chemical resistancy. It appears from the results that epoxy resins, DGEBA based polyamides can successf...

Novel Epoxy Curing Agents from Epoxy Resin Based Dialdehyde Derivative

Abstract A series of epoxy based curing agents were synthesised by the reaction of dialdehyde derivative 1, 1′-(1 -methylethylidene) di[4-{ 1-(1-imino-4-benzaldehyde)-2-propanolyloxy}] benzene of epoxy resin with a different aromatic diamines. The dialdehyde derivative was synthesised by the reaction of epoxy resin (DGEBA) with 4-amino benzaldehyde (4-ABA) in presence of triethyl amine (1% by wt. Of resin) as a catalyst. All this curing agents were characterised by their number average molecular weight (Mn), elemental analyses and infrared spectrophotometry (IR). As produced, polymers may act as a epoxy curing agent, the thermal characteristics of the synthesised PK-epoxy resin system were investigated by means of differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA).

Novel Metal Complex Based Epoxy Resin

Abstract The novel metal complex synthesized by the condensation reaction of metal chloride (NiCl2) with schiff base and hydroquinone (in 1:1:3 mole ratio) was epoxidized in presence of base catalyst to obtain metal complex based epoxy resin (i.e., Ni-epoxy). An attempt has been made to carry out comparative curing study (by DSC) for Ni-epoxy, diglycidylether of bisphenol-A (DGEBA) and triglycidylether of p-amino phenol (TGPAP) resin system using aliphatic and aromatic diamines as catalyst. On the basis of curing characteristics the mild steel panels were coated using all the three resins. The coated panels were tested for their flexibility, scratch hardness, impact strength and chemical resistancy.

Synthesis, characterization, and coating application of novel polyamines

A series of novel polyamine resins were synthesized by the preparation of ketimine terminated resins from ketimine blocked diethylene triamine (I) and bisester derivative (II) of epoxy resin and subsequent hydrolysis. I was synthesized by the condensation reaction of diethylene triamine with methyl isobutyl ketone. II was synthesized by the reaction of epoxy resin (DGEBA) with amino ethyl benzoate (AEB). The hydrolysis of ketimine containing resin was evaluated by the change in pH value of the reaction mixture, and by infrared spectroscopy and Gel Permeation Chromatography of the resulting product. The thermal stability and coating properties of the synthesized polyamines were studied in some detail. The hydrolytic rate of ketimine increased with increase temperature or the amount of added acid.

Novel Vinyl Ester Resin and its Urethane Derivatives

The epoxy resin, triglycidyl m-amino phenol, was reacted with acrylic acid to afford the vinyl ester resins. These vinyl ester resins were then reacted with toluenediisocyanate and hexamethylenediisocyanate to procure urethanized derivatives abbreviated as UTATGMAP and UTATGMAP* respectively. All these resins were characterized by their viscosity, number average molecular weight and infrared spectrophotometry. Curing characteristics for these resins were established by differential scanning calorimetry. The synthesized vinyl ester resin (TATGMAP) and urethane resins (UTATGMAP and UTATGMAP*) were polymerized on mild steel panels at 120 °C for 1 h. The resulting coated panels were characterized by scratch hardness, flexibility, impact strength and chemical resistance. The incorporation of styrene in the resin systems improves the properties of the coatings remarkably.