Experimental modeling of polymer latex spray coating for producing controlled-release urea

Lan, Rui; Liu, Yonghui; Wang, Guanda; Wang, Ting-Jie; Kan, Chengyou; Ye, Jin

doi:10.1016/j.partic.2011.01.004

Cited by 51 publications

(51 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The urea permeability with time for the aqueous solutions of urea + NaH 2 PO 4 . Compared with the data of urea permeability through some other polymer membranes that were reported previously, the values of permeability through PS membrane in the current study were higher than those of polyurethane membrane (almost 10 À6 cm 2 /day) in Watanabe's study [12] and those of latex membrane (almost 10 À4~1 0 À7 cm 2 /day) prepared from spry drying in Lan's study [13] , but were lower than those of N-phthaloyl acylated chitosan membrane (almost 4.9 × 10 À4 cm 2 /day or more) in Chen's study [32] . of 'constant-rate' release from saturated aqueous fertilizer solutions through the polymer coating to soil is the most important stage, because most amounts of the fertilizer nutrients are released in this stage.…”

Section: Saturated Solutionscontrasting

confidence: 59%

Permeation of fertilizer nutrients through polymer membrane: part I. Effect of P, K, and micronutrient fertilizer on permeability of urea

Liu

Sun

et al. 2016

Asia-Pacific J Chem Eng

View full text Add to dashboard Cite

The study aimed at investigating the addition effects of P, K, and micronutrient fertilizers on the permeability of N-nutrient fertilizer urea through a representative polymer membrane, which is of great importance in polymer-coated compound fertilizer. Specifically, the permeability of urea through polystyrene membrane was determined experimentally at the nominal temperature of 298 K using the Ussing chamber method for fertilizer solutions of urea-water, urea-NaH 2 PO 4 -water, urea-Ca(H 2 PO 4 ) 2 -water, urea-KCl-water, and urea-NaCl-water. The experimental data showed that the addition effects of NaH 2 PO 4 , KCl, and NaCl on urea permeability were pronounced and could be promotion or suppression depending on the amounts added. The variation of urea permeability with additive concentration could be explained by the 'solution-diffusion' model, suggesting that the specific intermolecular and interionic interactions in the permeation solution were an important factor determining the permeability. Using the saturated urea-water solution as basis, the addition of saturated KCl increased the urea permeability by 2.5 times, while the addition of saturated Ca(H 2 PO 4 ) 2 and NaH 2 PO 4 decreased the permeability by 41% and 76%, respectively.

show abstract

Section: Saturated Solutionscontrasting

confidence: 59%

Permeation of fertilizer nutrients through polymer membrane: part I. Effect of P, K, and micronutrient fertilizer on permeability of urea

Liu

Sun

et al. 2016

Asia-Pacific J Chem Eng

View full text Add to dashboard Cite

show abstract

“…Synthetic polymers have been employed as coating materials in various processes for the production of controlled-release fertilizers: (1) a polymer is dissolved in organic solvent and taken as the coating material [1][2][3]; (2) the coating material consists of multiple components that form polymer films with different thermosettings, such as a polyurethane (PU) film and an alkyd resin film [4][5][6]; and (3) polymer latex with water as the continuous phase is applied as a coating material by spraying the latex onto the surfaces of fertilizer particles to coat them with films after dehydration. This process is free of organic solvents and is considered promising as a green approach to producing controlled-release fertilizers [7][8][9].…”

Section: Introductionmentioning

confidence: 99%

Photodegradation of Polymer Materials Used for Film Coatings of Controlled‐Release Fertilizers

Yang

Wang

et al. 2017

Chem Eng & Technol

Self Cite

View full text Add to dashboard Cite

The photodegradation of three polymer materials was studied, i.e., polyolefin, polyurethane, and a copolymer of styrene, butyl acrylate, and methyl methacrylate (P(St-co-BA-co-MMA) latex). These polymers are mostly used as film-coating materials for producing controlled-release fertilizers. The P(St-co-BA-co-MMA) latex film degraded at the highest rate and the film surface became porous under UV irradiation. The weak cross-link chain in the latex film was broken and the connections between the microspheres were destroyed. A photo-oxidative aging reaction weakened the tenacity of the latex film, which resulted in the easy release of microspheres from the film, leading to a reduction in film thickness and film tensile strength. Threfore, P(St-co-BA-co-MMA) latex is a promising coating material for controlled-release fertilizers.

show abstract

“…In order to simulate the characteristics of the randomness, intermittence and multiple layers of the coating, and eliminate the effects of particle collision and increase the representativeness of coated film, an experimental simulation apparatus was used to prepare plane films by spraying so as to directly measure the film permeability coefficients [14]. The spray coating process, in a fluidized bed, is affected by many factors, and it lacks representative to characterize the film structures by using an individual coated film of a particle.…”

Section: Film Preparationmentioning

confidence: 99%

“…Plane films were prepared by spray coating in the experimental simulation apparatus [14]. The porosities of the plane films were measured by the porosimeter.…”

Section: Comparison Of Calculation and Measurementmentioning

confidence: 99%

Prediction of Release Characteristics of Film‐Coated Urea from Structure Characterization Data of the Film

et al. 2013

View full text Add to dashboard Cite

An efficient method for the prediction of the release characteristics of film-coated urea from its film structure is proposed. A model spray-coating apparatus was built to prepare a plane film to directly measure the film permeability coefficients by simulating the characteristics of randomness, intermittence and multiple layers of the coating, and eliminating particle collision effects. From analysis, the spraycoated film structure can be modeled as comprising a dense structure and a defect structure. Both structures contributed to the penetration flux and the apparent permeability coefficients of the film for water and urea diffusion. The permeability coefficients of the plane films were calculated from the film structure model, and were shown to be close to the measured values.

show abstract

Experimental modeling of polymer latex spray coating for producing controlled-release urea

Cited by 51 publications

References 6 publications

Permeation of fertilizer nutrients through polymer membrane: part I. Effect of P, K, and micronutrient fertilizer on permeability of urea

Permeation of fertilizer nutrients through polymer membrane: part I. Effect of P, K, and micronutrient fertilizer on permeability of urea

Photodegradation of Polymer Materials Used for Film Coatings of Controlled‐Release Fertilizers

Prediction of Release Characteristics of Film‐Coated Urea from Structure Characterization Data of the Film

Contact Info

Product

Resources

About