Study on the mechanism of PAMAM(DETA as the core) against silica scale.

Molecular simulation was performed to study the interaction between PAMAM(DETA as the core) with different generations and silicic acid molecules, and discussed the inhibition effect mechanism against silica scale through gyration radius and radial distribution function et al. The results showed that adsorption interactions between silicic acid molecules and the PAMAM with -NH terminated groups molecule (G1.0 and G2.

Rhodamine-Functionalized Mechanochromic and Mechanofluorescent Hydrogels with Enhanced Mechanoresponsive Sensitivity.

Smart materials responsible to external stimuli such as temperature, pH, solvents, light, redox agents, and mechanical or electric/magnetic field, have drawn considerable attention recently. Herein, we described a novel rhodamine (Rh) mechanophore-based mechanoresponsive micellar hydrogel with excellent mechanochromic and mechanofluorescent properties. We found with astonishment that, due to the favorable activation of rhodamine spirolactam in the presence of water, together with the stress concentration effect, the mechanoresponsive sensitivity of this hydrogel was enhanced significantly.

An Injectable, Dual Responsive, and Self-Healing Hydrogel Based on Oxidized Sodium Alginate and Hydrazide-Modified Poly(ethyleneglycol).

Oxidized sodium alginate is a handily modifiable polysaccharide owing to the pendant aldehyde groups which can form dynamic covalent bonds with amines, acylhydrazines, etc., providing oxidized sodium alginate-based hydrogels with stimuli-responsive properties. However, due to the stiffness and, in particular, the hydrophobicity of sodium alginate dialdehyde at low pH, the mechanical performance and pH stimuli responsiveness of oxidized sodium alginate-based hydrogels are still strictly limited.

Tough polypseudorotaxane supramolecular hydrogels with dual-responsive shape memory properties.

Cyclodextrin-polypseudorotaxane hydrogels have attracted extensive attention for their potential application in biomedical fields. Herein, we develop a facile strategy for the in situ formation of mechanically tough polypseudorotaxane hydrogels through photoinitiated copolymerization of poly(ethylene glycol) methyl ether methacrylate, acrylamide and sodium acrylate in α-CD solution at 60 °C. For the first time, we manage to screen the host-guest interaction between α-CD and PEG before copolymerization in the presence of a temporary hydrogen bonding weakening monomer (acrylamide) at a suitable temperature (60 °C).

Dual-responsive shape memory hydrogels with novel thermoplasticity based on a hydrophobically modified polyampholyte.

Shape memory hydrogels offer the ability to recover their permanent shape from temporarily trapped shapes without application of external forces. Here, we report a novel dual-responsive shape memory hydrogel with characteristic thermoplasticity. The water-insoluble hydrogel is prepared by simple ternary copolymerization of acrylamide (AM) and acrylic acid (AA) with low amounts of a cationic surfmer, in the absence of organic crosslinkers.

Shape Memory Hydrogel based on a Hydrophobically-Modified Polyacrylamide (HMPAM)/α-CD Mixture via a Host-Guest Approach.

A novel thermally sensitive shape memory (SM) hydrogel is prepared by block copoly-merization of a cationic surfactant monomer, dimethylhexadecyl[2-(dimethylamino)ethylmethacrylate]ammoniumbromide (C(16)DMAEMA), and acrylamide (AM) in the presence of α-cyclodextrin (α-CD) using N,N'-methylenebisacrylamide (MBA) as a crosslinker. XRD, solid state (13)C NMR, and DSC measurements show that the crystalline domains, induced by the hydrogen bonds between α-CDs threaded on the hydrophobic units of the polymer chains through the host-guest approach, can reversibly melt and crystallize at different temperatures. Rheological measurements show that both the elastic modulus G' and viscous modulus G'' drastically change due to the formation and dissolution of the crystalline domains.