Preparation and Properties of a Novel Semi-IPN Slow-Release Fertilizer with the Function of Water Retention

Abstract

A new semi-interpenetrating polymer network (semi-IPN) slow-release fertilizer (SISRF) with water absorbency, based on the kaolin-g-poly(acrylic acid-co-acrylic amide) (kaolin-g-P(AA-co-AM)) network and linear urea-formaldehyde oligomers (UF), was prepared by solution polymerization. Nutrients phosphorus and potassium were supplied by adding dipotassium hydrogen phosphate during the preparation process. The structure and properties of SISRF were characterized by various characterization methods. SISRF showed excellent water absorbency of 68 g g in tap water. The slow-release behavior of nutrients and water-retention capacity of SISRF were also measured. Meanwhile, the swelling kinetics was well described by a pseudo-second-order kinetics model. Results suggested the formation of SISRF with simultaneously good slow-release and water-retention capacity, which was expected to apply in modern agriculture and horticulture.

Preparation and anti‐evaporation properties of organic–inorganic superabsorbent based on Tragacanth gum and clay

“…The absorption peak of Si‐O‐Si at 1041 cm −1 in MMT was shifted to 1049 cm −1 in MMT (3%)‐SAP composite, and the absorption peak at 797 cm −1 disappeared, 22,30 which indicated that MMT was involved in the chemical reaction. In kaolin(3%)‐SAP composite, the absorption peaks at 788 cm −1 and 466 cm −1 were the stretching vibration of Si‐O‐Al and deformation vibration of Si‐O‐Si 23,31 respectively, thus, indicating that kaolin participated in the reaction. The absorption peak of APT(3%)‐SAP composite at 516 cm −1 represented the bending vibration of O‐Si‐O, 32 whereas the peak at 776 cm −1 was the deformation vibration of Si‐OH, 33 thus, indicating that APT was also involved in the reaction.…”

“…20 N-hydroxymethyl acrylamide (NHA) can crosslink the polysaccharide materials with poly(acrylic acid) to form the ether groups, and the resulting SAP network composed of the ether group is generally observed to be more easily degraded than the common N, N 0 -methylene acrylamide crosslinked superabsorbent network. 21 Clay-SAP composites (such as Kaolin, MMT and APT) composite materials demonstrate low cost, expansive properties, 22 gel strength and optimal salt resistance, 23 thus, such inorganic-organic composite materials have attracted widespread attention for commercial applications.…”

Preparation and performance of a kitchen waste oil‐modified polyvinyl alcohol‐grafted urea slow‐release fertilizer

“…For example, hydrogel MSRFs can maintain soil moisture while providing nutrients for plants, 13 but resistance to degradation still exists. Xiang Y et al 14 used superabsorbent resin and urea formaldehyde to prepare a new type of MSRF through graft copolymerization and semi‐interpenetrating technology. This fertilizer has the advantages of water absorption and moisture retention and a long release period.…”

Phosphates-Containing Interpenetrating Polymer Networks (IPNs) Acting as Slow Release Fertilizer Hydrogels (SRFHs) Suitable for Agricultural Applications

“…Such devices guarantee more effective, economical and environmentally beneficial nutrient uptake, as they prevent fertilizers from being leached from the soil [ 4 ]. Slow release fertilizer hydrogels (SRFHs) can be prepared using many different polymerization techniques, such as solution [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ] or inverse suspension polymerization [ 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ], as well as different mechanisms—free radical polymerization [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 16 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 ], RAFT polymerization [ 23 ], photopolymerization [ 15 , 17 , 26 ], etc. In general, there are several methods of SRFH preparation [ 3 ].…”