Polyether Amine Research Articles

New Polymeric Comb Dispersants for Agricultural Formulations: A Comparison of Performance in Pesticide Suspension Concentrates

Abstract A new family of dispersants for agrochemical suspension concentrate (SC) formulations has been created by reacting an anhydride-bearing resin with a methyl capped polyether amine. The result is a moderate molecular weight graft polyamide, with the desirable “comb” geometry. From this family of materials, four were chosen for comparison to three commercially available benchmark dispersants in several typical pesticide suspension concentrates. The criteria used to compare the new to the old dispersants were: ability to reduce suspension viscosity, zeta potential, syneresis, and tendency of the concentrate to “hardpack.” The study demonstrated that the new dispersants are generally very effective dispersants, but care must be used in selecting the best dispersant/wetting agent combination for a given pesticide formulation.

Novel epoxy compositions for vibration damping applications

AbstractThree epoxy compositions have been developed by using polyether amine hardeners having varying chain lengths of polyethers. Unlike normal epoxies, the compositions show low glass transition temperatures (0–45°C). Dynamic mechanical analysis and time–temperature superposition of the isotherms indicate that they have broad and high loss factor values over broad frequency and temperature ranges suggesting their application as viscoelastic materials in constrained layer damping of structural vibrations. Copyright © 2004 John Wiley & Sons, Ltd.

Influence of structure and chemical composition on oxygen permeability of crosslinked epoxy–amine coatings

The oxygen barrier properties of a series of coatings based on diglycidyl ethers of bisphenol and butanediol reacted with a wide range of amines in different stoichiometric ratios have been investigated. The oxygen permeability was analysed with respect to the molecular structure in general and the concentration of polar functional groups in particular. The results showed that formulations based on aliphatic amines gave good barrier performance, that coatings prepared from aromatic and cyclo-aliphatic amines yielded intermediate barrier properties, and that polyether amine formulations produced very poor barriers. It was also observed that pendant methyl groups had a strong detrimental effect on barrier properties and that using an excess of amine monomer significantly improved the barrier performance. Attempts at predicting the oxygen permeability from physical and chemical characteristics of the coatings showed that the glass transition temperature could not be correlated with the permeability. However, it was found that a polarity index, calculated as the sum of the concentrations of hydroxyl and amine moieties weighted by their individual cohesive energy density, was a good predictor of oxygen permeability for all types of formulations.

Effects of fuel additives on the microstructure of combustion engine deposits

The microstructure of spark-ignition (SI) engine deposits produced from fuels with two commonly used gasoline additives, polyether amine and polybutene amine, were studied by gas adsorption technique and Raman spectroscopy. The lateral sizes of graphitic crystallites were found to increase upon addition of the additives. The surface areas of the deposits were evaluated using the BET and DR theories. Density functional theory was used to evaluate pore size distribution. The majority of the internal surface area of the deposits is due to narrow pores of widths of about 0.5 nm. The surface area of the deposits decreases with increased concentration of the additives, and this process is more efficient for polybutene amines than polyether amines. The structure of the deposits removed from the combustion chamber’s cylinder heads is more porous than that of piston top deposits. Likewise, intake valve deposits were seen to be less porous than combustion chamber deposits.

Studies on the Modification of Thermoplastic Polyolefins (TPOs)—Part I. Effect of Various Modifiers on the Adhesion of a Two-Component (2K) Polyurethane Coating to the Modified TPOs

Thermoplastic polyolefins (TPOs) have low energy surfaces, therefore, they are difficult to be adhered to with adhesive and coating systems. Various modifiers, namely, polycaprolactone, polyvinyl acetate, poly(oxy-ethylene)glycol and polyamides were incorporated into the matrix of TPOs to modify and enhance their surface energy in order to improve adhesion of two component (2K) urethane coatings to their surface. Adhesion was investigated by using the crosshatch adhesion test. Good adhesion of 2K polyurethane coatings to the modified TPOs was achieved by using polyamides based on maleated polypropylene (MPP) and polyetheramine (PEA) (ED4000). The adhesion was found to be dependent on the modifier percentage and the equivalent ratio of MPP to PEA (ED4000).

Effect of addition of polyoxypropylenediamine on the morphology and mechanical properties of maleated polypropylene/maleated rubber blends

Blends of maleated polypropylene and maleated ethylene propylenediene (EPDM-g-MA) were compounded in a twin-screw extruder with a polyetheramine (PEA), polyoxypropylenediamine, as a compatibilizer. The effect of the compatibilizer concentration and molecular weight on the physical properties was investigated. FTIR data showed that the addition of the compatibilizer caused an imide linkage to form between the amine functionality on the PEA and the maleic anhydride (MA) functionality on both the polypropylene (PP) and the rubber backbone. This bond improved the interfacial adhesion between the rubber and the PP matrix, resulting in an improvement in the toughness of the blends. Other improvements in the physical properties of the blends with a compatibilizer compared to the blends without it included notched Izod impact, elongation at yield, and elongation at break. The optimum improvement in properties was found when the level of the compatibilizer was about 3 wt %. These changes in properties correlated well with the morphology observed via optical and scanning electron microscopy. © 1998 John Wiley & Sons, Inc. J Appl Polm Sci 68: 1451–1472, 1998

Transport of alkali metal cations through monoazacrown ether-modified Nafion TM 117 membrane

Conditions have been developed for the surface modification of Nafion TM 117 cation-exchange membrane by conversion to the sulfonyl chloride form and coupling with secondary amines to form sulfonamide groups. Nafion 117 membranes modified with diethylamine ( 13), dibutylamine ( 14), morpholine ( 15), bis(2-methoxyethyl)amine ( 16), and 8-aza-2,5,11, 14-tetraoxapentadecane ( 17), monoaza-12-crown-5 ( 18), monoaza-15-crown-5 ( 19), and monoaza-18-crown-6 ( 20) were prepared and their competitive, proton-coupled transport of alkali metal cations was compared with that of unmodified Nafion 117 membrane. Alkali metal cation permeation of membranes 13–16 was found to be poor. However, membranes 17–19 which were produced by coupling with an acyclic or cyclic polyether amine having more than three oxygen atoms gave efficient alkali metal cation permeation which was comparable with that for unmodified Nafion 117 membrane. The permeation selectivity order for these surface-modified Nafion 117 membranes was Cs +> Rb +> K +> Na +> Li + which differs from the ordering of K +> Rb +> Cs +> Na +> Li + observed for unmodified Nafion 117 membrane.

Poly(ether amide) triblock and star block copolymers

AbstractTriblock and three arm, poly(ether amide) star block copolymers have been synthesized and characterized. Di‐ and tri‐functional amine terminated polyethers were reacted with caprolactam at elevated temperatures to produce the block copolymers. The polyether amines were incorporated at levels ranging from 5%‐40%. Differential scanning calorimetry(DSC) evaluation reveals no reduction in the crystalline melting point of the polycaprolactam end blocks up to 40% polyether incorporation. Dynamic mechanical spectroscopy and FTIR were used to confirm the incorporation of the polyether. A comparison is made between triblock and star block copolymers, and between poly(propylene glycol) and poly(ethylene glycol) polyether midblocks. These block copolymers have improved impact performance as well as a flexural modulus that first increases and then decreases as the amount of polyether is increased in the block copolymer.

Separation of acetylated polypropylene glycol di- and triamines by gradient reversed-phase high-performance liquid chromatography and evaporative light scattering detection

Polypropylene glycol di- and triamines, the so-called Jeffamines, were reacted with a mixture of equal volumes of acetic anhydride and pyridine to give the corresponding acetamides prior to chromatographic separation by reversed-phase high-performance liquid chromatography using a linear binary solvent gradient and evaporative light scattering detection (ELSD). The procedure was applied to decrease silanophilic interactions of the solutes with the column matrix in order either to improve the peak resolution R s or to decrease peak tailing. Removal of excess of derivatizing agent prior to sample injection is not required owing to the volatility of pyridine, which does not yield any ELSD response. Therefore, the signals of oligomers with lower retention that are hidden by the broad and strongly tailing pyridine peak when measured by UV detection, are now clearly detectable. Separation was performed on C 18, C 8, C 6, C 4 and C 1 stationary phases with either acetonitrile or methanol as organic modifiers. With acetonitrile either complete elution or excellent separation of the low-molecular-mass samples ( M r ⋍ 400) is achieved on the C 18, C 8, C 6 and C 4 matrices. However, R s decreases with increasing M r but the recoveries of high- M r samples ( M r ⋍ 2000–5000) increase markedly with decreasing hydrophobicity of the stationary phase in the order C 18 < C 8 < C 6 < C 4. Complete elution of the whole family of investigated polyether amines was accomplished with either acetonitrile on a C 1 column or methanol on all sorbents used in the study. The optimum peak resolution was obtained on a C 4 column with either acetonitrile or methanol. Complete elution of all samples in particular on matrices with either high or intermediate hydrophobicity with methanol compared with acetonitrile is presumably attributable to a better solvation of the polypropylene glycol backbone by hydrogen bonding between the ether oxygens and the hydroxyl group of the protic solvent.

Secondary Aliphatic Polyether Amines for Polyurea RIM Systems

The excellent mechanical properties and high productivity of polyurea RIM systems allow for a broad variety of applications in the automo tive industry. Due to their high reactivity, however, these systems can lead to problems concerning the filling of large and complicated molds. Some years ago BASF/Elastogran introduced new polyurea/amide RIM systems (ELASTOLIT® R 4500 RIM series) based on polyether ketimines, which have reduced reactivity in comparison to polyethers with aliphatic pri mary amino end groups. This paper reports on research work for the new ELASTOLIT® R 4500/IF (Improved Flowability) RIM systems which are based on polyethers with secondary amino end groups. While mechanical properties remain at the level known from the polyurea RIM systems, the flowability and processability are superior even when compared to the polyether ketimine systems.

Modified Polyetheramines in RIM

Polyurea RIM, because of its production speed, internal release characteristics, high temperature dimensional stability, and increased resis tance to water absorption is finally coming to the forefront as a better route to producing automotive body panels and fascia. One of the barriers that held back the rapid replacement of polyurethane-urea RIM by this new technology has been the increased reaction rate typically exhibited by polyurea RIM. The throughputs of existing RIM equipment were not high enough to produce some of the larger fascia and body panel parts. To address this need of some molders to process polyurea RIM in lower throughput RIM machines, we have investigated various modifications of our polyetheramines. Among the modifications investigated were the recently in troduced ketimine technology, N-alkyl substituted polyetheramines and polyether amines having aromatic amine termination. The processing charac teristics and physical properties of some of these slower polyether amines in polyurea RIM formulations will be discussed.

A novel coating based on poly(etheramine-quinone) polymers

Commercially available polyetheramines, called Jeffamines, ∗∗ and p-benzoquinone react smoothly in alcoholic solution to yield linear polymers with interesting properties. One particular polymer, the product of polyether amine D400 : p-benzoquinone = 2:3, can displace water from wet, rusty metal surfaces. After heat curing, it is non-wettable, resists autoclaving, salt water spray and most common organic solvents and does not ice.

Polyurea RIM-A Versatile High Performance Material

Polyurethane elastomers were the first products to find wide commercial use in the RIM process. Recently, the advent of a new chain extender, diethyltolu enediamine (DETDA), provided another class of commercially useful RIM elas tomers. These materials are best classified as polyurethane/urea elastomers. We have been working on the next logical step in this evolution: amine- terminated polyether resins with amine chain extenders. These are best classi fied as polyurea elastomers. Amine-terminated polyether resins, or polyether polyamines, can replace the polyol in a RIM formulation. These materials are much more reactive than pol yols, and their composition can be varied more easily than conventional RIM polyols. Thus, these products can be tailored to meet the performance require ments of a particular end use more easily than polyols. The use of amine-terminated polyether products in RIM applications brings a new dimension to the RIM process. Depending on the choice of amine termi nated polyether amine, one can formulate systems covering a broad range of properties from elastomeric materials to rigid materials. Elastomeric materials are made by having a small amount of hard segment in a block-copolymer in conjunction with a polyether diamine. These elasto meric materials can be more closely tailored to meet a specific physical prop erty by either adjusting the formulation or by adjusting the density of the polymer. Very rigid materials can also be made by increasing the amount of hard seg ment in the block-copolymer in conjunction with a polyether triamine. High levels of an aromatic diamine chain extender can be used with the polyether triamine.

Improved resins for ion exchange with thermal regeneration

Abstract Ion-exchange desalting processes that operate on thermal regeneration would compete economically with membrane techniques if the pretreatment requirements are simplified and if the process operated in a continuous rather than batch mode. In this regard, significant developments in “Sirotherm” resins have been made. Firstly, the pretreatments have been reduced, in that it is now not necessary to remove alkalinity. However, pretreatments are essential for the removal of hardness cations and, for most waters other than anaerobic underground waters, for deoxygenation. Dosing with sodium sulfite is the most straightforward method of oxygen removal, and has required the synthesis of resins which are resistant to sulfite attack. High-capacity resins which are less easily oxidized are seen as the long-term solution. Polyether amine resins which are ten times more resistant to oxidation than the presently used resins show promises in this regard. Secondly, magnetic resins have been made and successfully tested on the pilot scale in a continuous countercurrent contactor of the fluid bed type. A 1 Ml/day demonstration plant is to be constructed. Present indications are that, for desalting low-salinity waters on the very large scale, the process will have a significantly lower capital cost than reverse osmosis.

Copolymerization of glycols with the divinyl ether of n-acetyldiethanolamine

The migration copolymerization of the divinyl ether of N-acetyldiethanolamine and a number of glycols to give polyether amines containing acetal groups was investigated.