Water-Soluble Urea-Formaldehyde Oligomers in Paint for Single-Firing Decoration of Ceramic

Abstract Wood polymer nanocomposites were prepared from solid aspen wood, water-soluble melamine-urea-formaldehyde (MUF) resin, and silicate nanoclays. The nanofillers were ground with a ball-mill before being mixed with the MUF resin and impregnated into the wood. The water-soluble prepolymer was mixed with the nanoclays at a mixing speed of 3050 rpm for 20 min to form impregnation solutions. Wood was impregnated with resin, which polymerized in situ under certain conditions. The physical and mechanical properties of the composite and the effect of ball-milling treatment of nanofillers on these properties were investigated. Significant improvements in physical and mechanical properties, such as density, surface hardness, and modulus of elasticity, were obtained for specimens impregnated with MUF resin and nanoclay-MUF resin mixtures. Ball-mill treatment favors dispersion of the nanofillers into the wood, but also appears to interfere with particle-resin adhesion.

Download Full-text

Liquid Chromatographic Determination of Urea in Water-Soluble Urea-Formaldehyde Fertilizer Products and in Aqueous Urea Solutions: Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/87.2.346 ◽

2004 ◽

Vol 87 (2) ◽

pp. 346-351 ◽

Cited By ~ 2

Author(s):

Michael M Hojjatie ◽

Dean E Abrams ◽

Thomas M Parham ◽

J Balthrop ◽

R Beine ◽

...

Keyword(s):

Urea Formaldehyde ◽

Collaborative Study ◽

Chromatographic Determination ◽

Sole Source ◽

Study Data ◽

Water Soluble ◽

Reaction Products ◽

Chromatography Method ◽

Commercial Products ◽

Aqueous Urea

Abstract Water soluble urea-formaldehyde (UF) fertilizers, manufactured by complex reaction of urea and form-aldehyde, typically contain varying amounts of unreacted urea. A liquid chromatography method for the analysis of urea in these products, and in aqueous urea solutions, was collaboratively studied. An amine chromatography column was used to separate the unreacted urea from numerous UF reaction products present in these liquid fertilizers. Unreacted urea was determined by using external urea standards with UV detection at 195 nm. The standards and test samples were prepared in the mobile phase of 85% (v/v) acetonitrile in water. Ten laboratories analyzed 5 different UF-based commercial products containing unreacted urea in the range of 6 to 17% by weight, and 5 different concentrations of urea in water equivalent to commercial products of that nature. The aqueous urea solutions contained 2–20% urea (w/w). The range of sR values for the 5 UF-based commercial fertilizers was 0.49–1.02 and the %RSDR was 1.94–6.14. The sR range for the 5 urea solutions was 0.10 to 0.79 and the %RSDR range was 2.54 to 4.88. The average recovery of urea from the aqueous urea solutions was 96–103%. Therefore, this method is capable of monitoring urea nitrogen manufacturers' label claims and total nitrogen claims in those cases where urea is the sole source of plant food nitrogen. Based on the collaborative study data, the authors recommend this method be approved for AOAC Official First Action status.

Download Full-text

Liquid Chromatographic Determination of Nitrogen Derived from Urea and Water-Soluble Methylene Ureas in Urea Formaldehyde Fertilizers: Collaborative Study II

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/67.4.768 ◽

1984 ◽

Vol 67 (4) ◽

pp. 768-770

Author(s):

Allan D Davidson ◽

◽

C Barry ◽

J Carmany ◽

A F Grigor ◽

...

Keyword(s):

Urea Formaldehyde ◽

Collaborative Study ◽

Chromatographic Determination ◽

Water Soluble ◽

Paired Samples ◽

Coefficients Of Variation ◽

Liquid Chromatographic Determination ◽

Aoac Official ◽

Liquid Chromatographic

Abstract A second collaborative study with 6 collaborators was conducted on the AOAC official first action method for measuring nitrogen derived from urea, methylenediurea (MDU), and dimethylenetriurea (DMTU). No variations were made. The collaborators made single determinations on 2 separate days on 5 sets of paired samples. The mean coefficients of variation for the completed study were 4.22% for urea, 5.08% for MDU, and 5.48% for DMTU, which are only slightly higher than the values reported in the first study: urea, 3.24%; MDU, 3.48%; and DMTU, 6.56%. The method has been adopted official final action.

Download Full-text

An Innovative Green Process for the Stabilization and Valorization of Organic Fraction of Municipal Solid Waste (OFMSW): Optimization of the Curing Process II Part

Applied Sciences ◽

10.3390/app9183702 ◽

2019 ◽

Vol 9 (18) ◽

pp. 3702 ◽

Cited By ~ 7

Author(s):

Carola Esposito Corcione ◽

Francesca Ferrari ◽

Raffaella Striani ◽

Paolo Visconti ◽

Antonio Greco

Keyword(s):

Mechanical Properties ◽

Municipal Solid Waste ◽

Solid Waste ◽

Urea Formaldehyde ◽

Complete Removal ◽

Water Soluble ◽

Curing Temperature ◽

Organic Fraction ◽

Neat Resin ◽

Selection Of

This work is focused on the optimization of an innovative and cheap process for the valorization of the organic fraction of municipal solid waste (OFMSW), through its transformation into an odorless and environmentally compatible material to be employed for building applications or as a thermal and acoustic insulator. The process starts with the grinding of OFMSW, followed by its sterilization in order to obtain a complete removal of the bacterial activity. Afterwards, the incorporation in a catalysed thermosetting matrix is carried out by mixing the OFMSW to a water soluble urea formaldehyde based resin (UF), characterized by a formaldehyde content lower than 1% wt. The OFMSW/UF blends were firstly analysed by the dynamic rheological analyses, as a function of the content of a proper catalyst, that is able to decrease the curing temperature and time. Rheological analyses results allowed the selection of times and temperatures necessary for the polymerization (T = 60 °C, t = 1 h). The effect of the presence of different additives on both the cure process and the mechanical properties of the cured samples was finally analysed, evidencing that the OFMSW/UF composites possess improved mechanical properties in comparison to that of the neat resin.

Download Full-text

Urea-Triazone N Characteristics and Uses

The Scientific World JOURNAL ◽

10.1100/tsw.2001.356 ◽

2001 ◽

Vol 1 ◽

pp. 103-107 ◽

Cited By ~ 2

Author(s):

John G. Clapp

Keyword(s):

Ammonia Volatilization ◽

Foliar Application ◽

Sandy Loam ◽

Urea Formaldehyde ◽

Stable Solution ◽

Water Soluble ◽

N Leaching ◽

Total N ◽

Available N ◽

N Source

Urea-triazone nitrogen (N) is a stable solution resulting from a controlled reaction in aqueous medium of urea, formaldehyde, and ammonia which contains at least 25% total N. This N source contains no more than 40%, nor less than 5%, of total N from unreacted urea and not less that 40% from triazone. All other N shall be derived from water-soluble dissolved reaction products of the above reactants. It is a source of slowly available N. The rate of mineralization of urea-triazone is about 66% that of urea after 8 days when incorporated in a Munjor sandy loam. Ammonia volatilization losses of N applied as urea-triazone were about 41% of those from urea on a Cecil sandy loam in the first week after application. N leaching losses through saturated Yolo loam columns of urea-triazone were about two thirds that of urea or nitrate N. This N source has proven to be a safer and more effective material for direct application on plant foliage. Tomato growth was enhanced with foliar application of urea-triazone relative to that obtained from ammonium nitrate or urea. The stability of this N source from potential losses via ammonia volatilization and nitrate leaching when soil applied is also documented by results from university trials.

Download Full-text

High Pressure Liquid Chromatographic Determination of Nitrogen Derived from Urea and Water-Soluble Methylene Ureas in Urea Formaldehyde Fertilizers: Collaborative Study

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/66.3.769 ◽

1983 ◽

Vol 66 (3) ◽

pp. 769-774

Author(s):

Allan D Davidson ◽

◽

E R Austin ◽

B M Christensen ◽

D Coggin ◽

...

Keyword(s):

High Pressure ◽

Urea Formaldehyde ◽

Collaborative Study ◽

Chromatographic Determination ◽

Water Soluble ◽

High Pressure Liquid Chromatographic ◽

Paired Samples ◽

Coefficients Of Variation ◽

Liquid Chromatographic Determination ◽

Liquid Chromatographic

Abstract A melhod for measuring nitrogen derived from urea, melhylenediurea (MDU), and dimethylenetriurea (DMTU) was tested by 9 collaborators. Collaborators made single determinations on 2 separate days on 5 sets of paired samples. Samples were extracted with water, filtered, and analyzed after high pressure liquid chromatographic separation on a C-8 or C-18 bonded silica column, using a refractive index detector. Peak heights compared to external standard of each component were used for quantitation. Mean coefficients of variation for the completed study were 3.24% for urea, 3.48% for MDU, and 6.56% for DMTU. The method has been adopted official first action.

Download Full-text

An Innovative Green Process for the Stabilization and Valorization of the Organic Fraction of Municipal Solid Waste

Applied Sciences ◽

10.3390/app9214516 ◽

2019 ◽

Vol 9 (21) ◽

pp. 4516 ◽

Cited By ~ 5

Author(s):

Carola Esposito Corcione ◽

Francesca Ferrari ◽

Raffaella Striani ◽

Stefania Minosi ◽

Mauro Pollini ◽

...

Keyword(s):

Thermal Treatment ◽

Municipal Solid Waste ◽

Solid Waste ◽

Organic Waste ◽

Urea Formaldehyde ◽

Construction Materials ◽

Complete Removal ◽

Water Soluble ◽

Organic Fraction ◽

Stabilization Phase

This work is aimed at the development of innovative, easy and cheap methods for the stabilization, inertization and valorisation of the organic fraction of municipal solid waste (OFMSW). For the first time, two original processes for transforming the organic waste into an inert, odorless and sanitized material were here proposed. The first one, called dual step, starts with grinding of the OFMSW, by means of an industrial shredder. After being finely ground, the organic waste was exposed to a sterilization process by means of UV/ozone radiations or thermal treatment (stabilization phase) in order to obtain a complete removal of the OFMSW’s bacterial activity. By means of several microbiological analyses, the best sterilization method was chosen. The incorporation in a thermosetting matrix was, then, carried out through mixing the sterilized and finely ground organic waste into a water soluble urea formaldehyde (UF) based resin, with a formaldehyde content less than 1% wt, followed by a thermal treatment for UF-resin crosslinking (inertization phase). An alternative cheaper and easier process, called one step, was also proposed and investigated, by combining the sterilization with the curing thermal process (at higher temperature) of the thermosetting matrix. The preliminary experimental results reported in this paper suggest that both the proposed methods could be considered suitable for the production of high valorized innovative OFMSW-derived panels or bricks that could find application in several fields, such as building or construction materials. Finally, a brief description of the prototype machinery, properly designed for implementing OFMSW stabilization and valorization processes, is reported.

Download Full-text

An Innovative Green Process for the Stabilization and Valorization of Organic Fraction of Municipal Solid Waste (OFMSW) I Part

10.20944/preprints201909.0284.v1 ◽

2019 ◽

Author(s):

Carola Esposito Corcione ◽

Francesca Ferrari ◽

RAFFAELLA STRIANI ◽

Stefania Minosi ◽

Mauro Pollini ◽

...

Keyword(s):

Thermal Treatment ◽

Municipal Solid Waste ◽

Solid Waste ◽

Organic Waste ◽

Urea Formaldehyde ◽

Research Work ◽

Complete Removal ◽

Water Soluble ◽

Organic Fraction ◽

Stabilization Phase

This work is aimed at the development of innovative, easy and cheap methods for the stabilization, inertization and valorisation of the organic fraction of municipal solid waste (OFMSW). For the first time, two original processes for transforming the organic waste into an inert, odorless and sanitized material were here proposed. The first one, called dual step, starts with grinding of the OFMSW, by means of an industrial shredder. After being finely ground, the organic waste was exposed to a sterilization process by means of UV/ozone radiations or thermal treatment (stabilization phase) in order to obtain a complete removal of the OFMSW’s bacterial activity. By means of several microbiological analyses, the best sterilization method was chosen. The incorporation in a thermosetting matrix was, then, carried out through mixing the sterilized and finely ground organic waste into a water soluble urea formaldehyde (UF) based resin, with a formaldehyde content less than 1% wt, followed by a thermal treatment for UF-resin crosslinking (inertization phase). An alternative cheaper and easier process, called one step, was also proposed and investigated, by combining the sterilization with the curing thermal process (at higher temperature) of the thermosetting matrix. The preliminary experimental results reported in this paper suggest that both the proposed methods could be considered suitable for the production of high valorized innovative OFMSW-derived panels or bricks, that could find application in several fields, such as building or constructions materials. Finally a brief description of the prototype machinery is reported properly designed for implementing OFMSW stabilization and valorisation processes developed in this research work.

Download Full-text

System for the Determination of the Potential Degradability of Urea-Aldehyde Condensates Used as Fertilizers

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/50.4.975 ◽

1967 ◽

Vol 50 (4) ◽

pp. 975-980

Author(s):

Stanley E Katz ◽

Carol A Fassbender

Keyword(s):

Urea Formaldehyde ◽

Oxygen Demand ◽

Water Soluble ◽

Microbial Cultures ◽

Potential Availability ◽

Agronomic Potential ◽

Mixed Microbial Cultures ◽

Nitrogen Sample ◽

Theoretical Amount

Abstract A solution biodegradability system, based upon the biochemical oxygen demand principle, narrower fractionation of materials, and use of microbial cultures adapted to these individual fractions, was developed to determine potential availability. Urea-formaldehyde condensates were fractionated into five fractions: the 25°C water-soluble fraction, the fraction insoluble at 25°C but soluble at 50°C, the fraction insoluble at 50 °C but soluble at 75 °C, the fraction insoluble at 75°C but soluble at 100°C, and the fraction insoluble at 100°C. Mixed microbial cultures were developed to utilize the nitrogen in these fractions as a source of nitrogen. Degradation studies of these fractions showed that each fraction used 90—100% of the theoretical amount of nitrogen. Sample sizes as large as 0.2 g of ureaform can be used. When this system was applied to the urea-crotonaldehyde condensate used as a fertilizer, results showed that 90—105% of the nitrogen was utilizable. These biodegradability principles are useful in determining the potential degradability of any urea-aldehyde condensate showing agronomic potential.

Download Full-text

SOFTWOOD COMPOSITES FOR CONSTRUCTION

10.34220/mmeitsic2021_74-79 ◽

2021 ◽

Author(s):

A.A. Lukash ◽

◽

N.P. Lukuttsova ◽

K.P. Kolotvin ◽

K.V. Razrezov ◽

...

Keyword(s):

Industrial Waste ◽

Building Materials ◽

Urea Formaldehyde ◽

Negative Influence ◽

Water Soluble ◽

Winter Period ◽

Composite Manufacturing ◽

Secondary Use ◽

Wood Consumption ◽

Manufacturing Mode

The article deals with the issues of secondary use of industrial waste from the processing of soft hardwood wood. It is shown that the disposal of man-made waste in landfills is undesirable, and the use of wood waste to generate heat for heating is limited to the autumn-winter period. It is proved that it is most expedient to make composites from the waste of processing soft hardwood wood, since the need for inexpensive building materials is constantly increasing. Wood- cement materials from soft-leaved wood are practically not produced due to the presence of water- soluble saccharides, which worsen the process of hydration of cement. It is proposed to use binders that harden quickly in the production of composites made of soft hardwood. To exclude the negative influence of the extracted substances, it is proposed to use urea-formaldehyde glue as a binder. The mathematical dependence of the compressive strength of a composite made of soft hardwood on the glue consumption, wood consumption and the duration of exposure after molding is obtained. The parameters of the composite manufacturing mode are set: wood consumption-190 ... 195 kg/m3, urea-formaldehyde glue consumption-262...270 kg/m3; the duration of exposure after molding – 6 days. Methods for reducing the release of free formaldehyde from composites have been identified. It was found that in the steam-air mixture after 12 days of exposure of the chip-and- glue composite, there are no previously detected micro-impurities of formaldehyde, and the chip- and-glue composite can be used in construction without restrictions.

Download Full-text