Water Retaining Agent

Introduction

Water retaining agent, also known as soil water retaining agent or superabsorbent resin, is a typical functional polymer material composed of large molecule polymer with hydrophilic linear or branched chain. Its molecular structure has been usually designed with a certain degree of crosslinking, generally a three-dimensional network structure. Due to its molecular chain with many hydrophilic groups, such as hydroxyl group, carboxyl group, amino group, etc., it can quickly absorb hundreds to thousands of times its own volume and weight of water. After that, the gel of water retaining agent can slowly release the stored water to supply water to the crops, thus achieving the purpose of water conservation. Water retaining agent as a chemical water saving technology can enhance soil water retention, improve soil physical and chemical properties, reduce soil moisture loss of nutrients, improve the utilization rate of water, promote root growth and increase crop yield. Therefore, it widely used in desert control, soil improvement, urban greening, lawn maintenance, etc.

Classification

According to the source of raw materials, water retaining agent can be mainly divided into the four categories of starch and its derivatives, cellulose and its derivatives, polyacrylic acid series and polyamino acids.

Starch and its derivatives: The series of water retaining agents are the substance with many hydroxyl groups, which are made from the biodegradable, rich source and low-cost starch as raw materials. At present, the main research of the series of water retaining agents is graft polymerization of starch by acrylamide or acrylic acid.
Cellulose and its derivatives: Cellulose is abundant in sources and has a high salt tolerance, however, its water absorption capacity is not strong. So many studies improved its performance by adding different ionic or non-ionic hydrophilic groups on its structure through chemical modification. In addition, cellulose can be copolymerized with acrylic acid, ethylene glycol and other monomers to obtain efficient water retention agent.
Polyacrylic acid series: The series of water retaining agents are obtained by copolymerization of acrylic acid (salts) with other monomers containing hydrophilic groups. They have the good performance with water absorption of more than 1000 times and have become the mainstream water retention agent at present.
Polyamino acids: The series of water retaining agents have the structure of natural polyamino acid chain and begin to rise in recent ten years. Because the main chain contains a large number of peptide bonds and the side chain contains rich hydrophilic groups, the product with strong water absorption can be obtained through moderate cross-linking. The water absorption can reach 2000-3000 times of its own volume. Common products are polyglutamic acids, polylysines, and polyaspartic acids.

Mechanism

In water retaining agent, the molecular chain is connected indefinitely and with the complex three-dimensional network structure. The structure makes water retaining agent has a certain degree of crosslinking. The cross-linked network structure has many hydrophilic groups such as carboxyl groups and hydroxyl groups. When it comes into contact with water, the hydrophilic groups on its molecular surface can ionize and bond with water molecules through hydrogen bonds, holding a large amount of water in this way.

Mechanism

Our Products

Alfa Chemistry is committed to the field of soil remediation and has successfully developed a variety of water retaining agents. Some of them are as follows.

ACMWRA-PP

	ACMWRA-PP-01	ACMWRA-PP-02	ACMWRA-PP-03
Main components	Potassium polyacrylate	Potassium polyacrylate	Potassium polyacrylate
Appearance	White translucent uniform small particles	White translucent uniform particles	White translucent uniform particles
Particle size (mm)	0.18-1.2	1.2-2	2-10
Water absorption ratio (deionized water) (g/g)	500-600	450-550	400-500
After water absorption	A pasty gel	Gel with high strength and toughness	Gel with high strength and toughness
pH	6.0-8.0	6.0-8.0	6.0-8.0
Solid content	≥90%	≥90%	≥90%
Active components	≥99%	≥99%	≥99%
Shelf life	Store in room against moisture and light for 3 years	Store in room against moisture and light for 3 years	Store in room against moisture and light for 3 years
Applications	It can be used for soil-water conservation, soil conditioning, soilless cultivation, seedlings transplanting, dipping roots, fertilizer additives, etc.	It can be used for soil-water conservation, soil conditioning, large crops, seedlings transplanting, fertilizer additives, etc.	Fruit tree special water retaining agent.

ACMWRA-PAA

	ACMWRA-PAA-01	ACMWRA-PAA-02	ACMWRA-PAA-03	ACMWRA-PAA-04
Main components	Acrylate / acrylamide copolymer	Acrylate / acrylamide copolymer	Acrylate / acrylamide copolymer	Acrylate / acrylamide copolymer
Appearance	Granule	Granule	Granule	Powder
Particle size (%)	10-100mesh≥80	10-20mesh≥80	20-40mesh≥80	40-100mesh≥80
Water absorption ratio (deionized water) (g/g)	≥400	≥400	≥400	≥350
Absorbance of 0.9％NaCl (g/g)	≥50	≥50	≥50	≥45
pH	6.0-8.0	6.0-8.0	6.0-8.0	6.0-8.0
Moisture (%)	≤8.0	≤8.0	≤8.0	≤8.0
Applications	It is mainly used for gardening and household planting, etc.	It is mainly used for afforesting, landscaping, and desert healing, etc.	It is mainly used for crops planting, seedling, and sodding, etc.	It is mainly used for root moistening, seed clothing, and seed shaping, etc.

Alfa Chemistry is committed to environmental governance field and focuses on providing comprehensive and high-quality products of water retaining agent. If you can't find the product what you're looking for in our product catalogue, we can also provide you with customized service. Please contact us, if you have any needs.

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