Hydrogel agriculture

Last updated

Common hydrogel agriculture's ingredient is potassium polyacrylate or sodium polyacrylate. As a superabsorbent material, it can absorb plenty of water and turn water to gel to store water.

Contents

Hydrogel agriculture technology uses insoluble gel-forming polymers to improve the water-holding properties of different soils, such as clays and sandy loams. This can increase water-holding and water use (up to 85% for sand), improve soil permeability, reduce the need for irrigation, reduce compaction, soil erosion, and leaching, and improve plant growth.

Desertification and lack of water threaten agriculture in many arid and semi-arid regions of the world; these may be mitigated with hydrogels. [1]

Hydrogels

Hydrogels are hydrophilic crosslinked polymers that form three-dimensional molecular networks which can absorb and hold great amounts of water. [2]

Different types may be suitable for agricultural use. A starch-based (grafing) hydrogel is biodegradable and cheap, and can be modified to adjust its ability to hold water. [3] Cross-linked acrylic acid polymer hydrogels are commercially available; they are effectively insoluble [4] but slowly break down releasing toxic acrylamide. [5]

Potential uses in agriculture

Hydrogels of different kinds could be useful in agriculture, reducing drought stress in plants, making better use of irrigation water and fertilizer. [6] [7] [8]

Superabsorbent hydrogel polymers can in principle influence soil permeability, density, structure, texture, evaporation and infiltration rates of water through soils. [7] They can also allow pesticides to be released slowly over a long period, increasing effectiveness and reducing side-effects such as pesticide runoff. There has therefore been considerable research interest into the possible use of hydrogels in agriculture. [9] For example, a hydrogel based on gum tragacanth increases the water content of clay soil by up to 5.35% and of sandy loam by up to 5.5%; it could also be used to release calcium chloride slowly over a prolonged period. [10]

Suitably prepared hydrogels can simultaneously supply and slowly release pesticides (such as herbicides) in the soil, and increase a sandy soil's retention of water. Hydrogels developed for this purpose include polymers of oligooxyethylene methacrylate, linked by ionic and covalent bonds to a herbicide such as 4-chloro-2-methylphenoxyacetic acid (CMPA). Other hydrophilic polymers studied have been made from a variety of different acrylate monomers to release the pesticides 2,4-D and CMPA. These offer different combinations of pesticide release rate and soil water retention. Hydrogels can also be used to encapsulate the insecticide cypermethrin and the fungicide copper sulphate. Superabsorbent polymers can be used to release phosphate fertiliser slowly, by making an ester bond between polyvinyl alcohol and phosphoric acid. A polymer/clay superabsorbent composite material made by attaching acrylamide to finely powdered attapulgite (a fuller's earth clay) shows promise for its excellent water retention and low cost compared to polyacrylamide hydrogel. [8]

Commercialization

In 2015, The Indian Agriculture Research Institute (IARI) reported the development of a novel hydrogel for agricultural use. It was intended to help farmers to cope with drought, making efficient use of water in arid and semi-arid regions of India. the product is to be commercialized by the Ministry of Science and Technology's National Research Development Corporation (NRDC) in collaboration with a company based in Chennai, Reliance Industries Limited. [11]

See also

Related Research Articles

<span class="mw-page-title-main">Aspartic acid</span> Amino acid

Aspartic acid, is an α-amino acid that is used in the biosynthesis of proteins. The L-isomer of aspartic acid is one of the 22 proteinogenic amino acids, i.e., the building blocks of proteins. D-aspartic acid is one of two D-amino acids commonly found in mammals. Apart from a few rare exceptions, D-aspartic acid is not used for protein synthesis but is incorporated into some peptides and plays a role as a neurotransmitter/neuromodulator.

Acrylates are the salts, esters, and conjugate bases of acrylic acid. The acrylate ion is the anion CH2=CHCO−2. Often, acrylate refers to esters of acrylic acid, the most common member being methyl acrylate. These acrylates contain vinyl groups. These compounds are of interest because they are bifunctional: the vinyl group is susceptible to polymerization and the carboxylate group carries myriad functionalities.

<span class="mw-page-title-main">Polyacrylamide</span> Chemical compound

Polyacrylamide (abbreviated as PAM or pAAM) is a polymer with the formula (-CH2CHCONH2-). It has a linear-chain structure. PAM is highly water-absorbent, forming a soft gel when hydrated. In 2008, an estimated 750,000,000 kg were produced, mainly for water treatment and the paper and mineral industries.

<span class="mw-page-title-main">Hydrogel</span> Soft water-rich polymer gel

A hydrogel is a biphasic material, a mixture of porous and permeable solids and at least 10% of water or other interstitial fluid. The solid phase is a water insoluble three dimensional network of polymers, having absorbed a large amount of water or biological fluids. Hydrogels have several applications, especially in the biomedical area, such as in hydrogel dressing. Many hydrogels are synthetic, but some are derived from natural materials. The term "hydrogel" was coined in 1894.

A soil conditioner is a product which is added to soil to improve the soil’s physical qualities, usually its fertility and sometimes its mechanics. In general usage, the term "soil conditioner" is often thought of as a subset of the category soil amendments, which more often is understood to include a wide range of fertilizers and non-organic materials. In the context of construction soil conditioning is also called soil stabilization.

<span class="mw-page-title-main">Sodium polyacrylate</span> Anionic polyelectrolyte polymer

Sodium polyacrylate (ACR, ASAP, or PAAS), also known as waterlock, is a sodium salt of polyacrylic acid with the chemical formula [−CH2−CH(CO2Na)−]n and has broad applications in consumer products. This super-absorbent polymer (SAP) has the ability to absorb 100 to 1000 times its mass in water. Sodium polyacrylate is an anionic polyelectrolyte with negatively charged carboxylic groups in the main chain. It is a polymer made up of chains of acrylate compounds. It contains sodium, which gives it the ability to absorb large amounts of water. When dissolved in water, it forms a thick and transparent solution due to the ionic interactions of the molecules. Sodium polyacrylate has many favorable mechanical properties. Some of these advantages include good mechanical stability, high heat resistance, and strong hydration.

<span class="mw-page-title-main">Acrylate polymer</span> Group of polymers prepared from acrylate monomers

An acrylate polymer is any of a group of polymers prepared from acrylate monomers. These plastics are noted for their transparency, resistance to breakage, and elasticity.

QPNC-PAGE, or QuantitativePreparativeNativeContinuousPolyacrylamideGel Electrophoresis, is a bioanalytical, one-dimensional, high-resolution and high-precision electrophoresis technique applied in biochemistry and bioinorganic chemistry to quantitatively separate proteins by isoelectric point and by continuous elution from a gel column.

<span class="mw-page-title-main">Superabsorbent polymer</span> Polymers that absorb and retain extremely large amounts of liquid

A superabsorbent polymer (SAP) (also called slush powder) is a water-absorbing hydrophilic homopolymers or copolymers that can absorb and retain extremely large amounts of a liquid relative to its own mass.

Solution polymerization is a method of industrial polymerization. In this procedure, a monomer is dissolved in a non-reactive solvent that contains a catalyst or initiator.

<span class="mw-page-title-main">Polyacrylic acid</span> Anionic polyelectrolyte polymer

Poly(acrylic acid) (PAA; trade name Carbomer) is a polymer with the formula (CH2−CHCO2H)n. It is a derivative of acrylic acid (CH2=CHCO2H). In addition to the homopolymers, a variety of copolymers and crosslinked polymers, and partially deprotonated derivatives thereof, are known and of commercial value. In a water solution at neutral pH, PAA is an anionic polymer, i.e., many of the side chains of PAA lose their protons and acquire a negative charge. Partially or wholly deprotonated PAAs are polyelectrolytes, with the ability to absorb and retain water and swell to many times their original volume. These properties – acid–base and water-attracting – are the bases of many applications.

Poly(N-isopropylacrylamide) (variously abbreviated PNIPA, PNIPAM, PNIPAAm, NIPA, PNIPAA or PNIPAm) is a temperature-responsive polymer that was first synthesized in the 1950s. It can be synthesized from N-isopropylacrylamide which is commercially available. It is synthesized via free-radical polymerization and is readily functionalized making it useful in a variety of applications.

<i>N</i>,<i>N</i>-Methylenebisacrylamide Chemical compound, polyacrylamide crosslinker

N,N′-Methylenebisacrylamide (MBAm or MBAA, colloquially "bis") is the organic compound with the formula CH2[NHC(O)CH=CH2]2. A colorless solid, this compound is a crosslinking agent in polyacrylamides, e.g., as used for SDS-PAGE.

<span class="mw-page-title-main">2-Acrylamido-2-methylpropane sulfonic acid</span> Chemical compound

2-Acrylamido-2-methylpropane sulfonic acid (AMPS) was a Trademark name by The Lubrizol Corporation. It is a reactive, hydrophilic, sulfonic acid acrylic monomer used to alter the chemical properties of wide variety of anionic polymers. In the 1970s, the earliest patents using this monomer were filed for acrylic fiber manufacturing. Today, there are over several thousands patents and publications involving use of AMPS in many areas including water treatment, oil field, construction chemicals, hydrogels for medical applications, personal care products, emulsion coatings, adhesives, and rheology modifiers. Lubrizol discontinued the production of this monomer in 2017 due to copy-cat production from China and India destroying the profitability of this product.

Smart polymers, stimuli-responsive polymers or functional polymers are high-performance polymers that change according to the environment they are in.

Xploderz is a line of toy weapons made by The Maya Group to compete with Hasbro's Nerf Super Soaker line and marketed as a safer alternative to paintball. The concept is based on Orbeez, a toy line also by The Maya Group that uses water-absorbent gel pellets, and hence the toy line is sometimes referred to as "Orbeez ball shooters".

<span class="mw-page-title-main">SNF Floerger</span>

SNF is one of the largest manufacturers of polyacrylamides. These water-soluble polymers are used as flocculants and coagulants in solid/water separation to recycle water, rheology modifiers and friction reducers. These functionalities have many uses where water is used, in drinking water production, wastewater treatment, mining, paper, enhanced oil recovery, hydraulic fracturing, agriculture, textile and cosmetics.

<span class="mw-page-title-main">Polyaspartic acid</span> Chemical compound

Polyaspartic acid (PASA) is a biodegradable, water-soluble condensation polymer based on the amino acid aspartic acid. It is a biodegradable replacement for water softeners and related applications. PASA can be chemically crosslinked with a wide variety of methods to yield PASA hydrogels. The resulting hydrogels are pH-sensitive such that under acidic conditions, they shrink, while the swelling capacity increases under alkaline conditions.

<span class="mw-page-title-main">Polymer soil stabilization</span> Engineering technique

Polymer soil stabilization refers to the addition of polymers to improve the physical properties of soils, most often for geotechnical engineering, construction, or agricultural projects. Even at very small concentrations within soils, various polymers have been shown to increase water retention and reduce erosion, increase soil shear strength, and support soil structure. A wide range of polymers have been used to address problems ranging from the prevention of desertification to the reinforcement of roadbeds.

<span class="mw-page-title-main">Potassium polyacrylate</span> Chemical compound

Potassium polyacrylate is a potassium salt of polyacrylic acid with the chemical formula [−CH2−CH(CO2K)−]n. As a type of superabsorbent polymer, it can absorb hundreds of times its original weight in purified water.

References

  1. ↑ Vundavallia, Ramesh (2015). "Biodegradable Nano-Hydrogels in Agricultural Farming-Alternative Source For Water Resources". Procedia Materials Science. 10: 548–554. doi: 10.1016/j.mspro.2015.06.005 .
  2. ↑ Ahmed, Enas M. (2015). "Hydrogel: Preparation, characterization, and applications: A review". Journal of Advanced Research. 6 (2): 105–121. doi:10.1016/j.jare.2013.07.006. PMC   4348459 . PMID   25750745.
  3. ↑ Jyothi, A.N. (2010). "Starch Graft Copolymers: Novel Applications in Industry". Composite Interfaces. 17 (2–3): 165–174. Bibcode:2010ComIn..17..165J. doi:10.1163/092764410X490581. S2CID   94545528.
  4. ↑ "Acrylic acid polymer, neutralized, cross-linked". Occupational Toxicants. 15: 1–29. 31 January 2012. doi: 10.1002/3527600418.mb900301nete0015 . ISBN   978-3527600410.
  5. ↑ Cheng, Peiyao (2004). Chemical and photolytic degradation of polyacrylamides used in potable water treatment. University of South Florida (PhD Thesis).
  6. ↑ Narjari, Bhaskar; Aggarwal, Pramila; Kumar, Satyendra; M.D, Meena (2013). "Significance of Hydrogel and its application in agriculture". Indian Farming. 62 (10): 15–17.
  7. 1 2 L. O., Ekebafe; Ogbeifun, D. E.; Okieimen, F. E. (2011). "Polymer Applications in Agricultur e". Biokemistri. 23: 81–89.
  8. 1 2 Puoci, Francesco; et al. (2008). "Polymer in Agriculture: A Review" (PDF). American Journal of Agricultural and Biological Sciences. 3 (1): 299–314. doi: 10.3844/ajabssp.2008.299.314 .
  9. ↑ Rudzinski, W. E.; et al. (2002). "Hydrogels as controlled release devices in agriculture: Review". Designed Monomers and Polymers. 5 (1): 39–65. doi:10.1163/156855502760151580. S2CID   101877671.
  10. ↑ Suruchinit, J.; Kaith, Balbir Singh; Jindal, Rajeev; Kapur, G. S.; Kumar, Vaneet (2014). "Synthesis, characterization and evaluation of Gum tragacanth and acrylic acid based hydrogel for sustained calcium chloride release – enhancement of water-holding capacity of soil". Journal of the Chinese Advanced Materials Society. 2 (1): 40–52. doi:10.1080/22243682.2014.893412.
  11. ↑ Mohan, Vishwa (15 January 2015). "Hydrogel agriculture technology". Times of India.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.