CN-121975295-A - Biosafety PEG-based phase-change hydrogel and preparation method thereof

CN121975295ACN 121975295 ACN121975295 ACN 121975295ACN-121975295-A

Abstract

The invention discloses a biosafety PEG-based phase-change hydrogel and a preparation method thereof, wherein the phase-change hydrogel is constructed by polyethylene glycol, biomacromolecules with a plurality of primary amino groups and an aldehyde polysaccharide derivative through in-situ crosslinking reaction in aqueous medium, forms a dynamic covalent network through dynamic Schiff base reaction between aldehyde groups and primary amino groups, and forms a double-network structure in cooperation with a wide hydrogen bond physical network among all components. The structure can firmly encapsulate the PEG phase change unit, effectively prevent the PEG phase change unit from leaking in water environment or high temperature, keep the high phase change enthalpy of PEG to the greatest extent, and simultaneously endow the material with excellent self-healing capability. The phase-change hydrogel prepared by the invention has good biocompatibility, proper mechanical property and intelligent moisture management function, and is particularly suitable for being used as a medical dressing matrix material for wound care requiring local thermal management and wet environment management.

Inventors

HUANG QUE
YANG JINLU
LIU CHANGCHENG
GUO LI
ZHANG WENYUE
ZHANG JIACHEN
LI JINHU

Assignees

中南大学
中北大学
山西医科大学第一医院

Dates

Publication Date: 20260505
Application Date: 20260129

Claims (9)

1. A biosafety PEG-based phase-change hydrogel is constructed by in-situ crosslinking reaction of raw materials containing the following components in an aqueous medium: (a) Polyethylene glycol with the number average molecular weight of 400-1000 Da is used as a phase-change heat storage functional unit; (b) A biomacromolecule having a plurality of primary amino groups as a main polymer skeleton for constructing a hydrogel; (c) An aldehyde group functional group is modified on the molecular chain of the aldehyde polysaccharide derivative; A dynamic covalent cross-linking network is constructed by forming a dynamic Schiff base bond between an aldehyde group on the component (c) and a primary amino group on the component (b), and a physical cross-linking network is constructed by wide hydrogen bond interaction between the components (a), (b), (c) and water, so that a composite hydrogel system which is used for firmly packaging the component (a) and has self-healing performance and a thermal management function is formed.
2. The PEG-based phase change hydrogel of claim 1, wherein the PEG-based phase change hydrogel has a water content of 75-80%.
3. The PEG-based phase change hydrogel according to claim 1, wherein the feeding mass ratio of the polyethylene glycol to the biomacromolecule having a plurality of primary amino groups and the aldehyde polysaccharide derivative is 5:0.8-1.2:0.8-1.2.
4. The PEG-based phase change hydrogel according to claim 1,2 or 3, wherein the biomacromolecule having a plurality of primary amino groups is selected from one or more of gelatin, collagen, aminated sodium alginate.
5. A PEG-based phase change hydrogel according to claim 1,2 or 3, characterized in that said aldehyde polysaccharide derivative is selected from one or more of oxidized carboxymethyl cellulose, oxidized sodium alginate, oxidized hyaluronic acid, oxidized hydroxyethyl cellulose.
6. The method for preparing the PEG-based phase-change hydrogel according to any one of claims 1 to 5, which is characterized in that: preparing respective uniform aqueous solutions from the polyethylene glycol, the biomacromolecule with a plurality of primary amino groups and the aldehyde polysaccharide derivative; Uniformly mixing the aqueous solutions under stirring to obtain a precursor solution; and standing the precursor solution at room temperature, and curing to form the phase-change hydrogel.
7. The method for preparing a PEG-based phase-change hydrogel according to claim 6, wherein the aqueous solutions are stirred and mixed for not less than 30 minutes to obtain a precursor solution.
8. The method for preparing the PEG-based phase-change hydrogel according to claim 6, wherein the curing time is 2-5 h.
9. The use of the PEG-based phase change hydrogel according to claim 1 as a medical dressing matrix material.

Description

Biosafety PEG-based phase-change hydrogel and preparation method thereof Technical Field The invention belongs to the technical field of hydrogel composite phase change materials, and relates to a biocompatible hydrogel material which is built by packaging phase change units through a dynamic reversible cross-linked network and has intrinsic self-healing capacity, excellent leakage resistance and stable thermal management performance, and a preparation method thereof. Background In the fields of medical care, sports protection and the like, durable and safe human body thermal management technology is increasingly attracting attention. The traditional cooling materials, such as ice bags or cooling sprays, often have the problems of inaccurate temperature control, short duration time, poor biological safety and the like, and the development of novel thermal management materials with high-efficiency thermal regulation capability, durability, stability and biological safety becomes a research hot spot. Phase Change Materials (PCMs) are considered ideal thermal management media because they can absorb or release a large amount of latent heat at approximately constant temperature during phase change, and have the characteristics of small temperature fluctuation and high energy storage density. Among them, polyethylene glycol (PEG) is known for its high enthalpy of phase transition, good water solubility and excellent biosafety. However, PEG is prone to liquid phase leakage when solid-liquid phase changes occur, severely limiting its immediate use. Encapsulation of PEG in a three-dimensional hydrogel network is an effective strategy to solve its leakage problem and at the same time impart flexibility and skin-friendly properties to the material. Hydrogels are composed of three-dimensional network structures of hydrophilic polymers and water, which can effectively encapsulate functional molecules, and high water content, biocompatibility and low toxicity have also made them of interest in the biomedical field. However, the current common technical path for constructing PEG-based phase-change hydrogel solves the problem of liquid phase leakage, and simultaneously generally introduces new significant performance defects: Physical blending/embedding strategy this method typically physically adsorbs or embeds PEG solutions in preformed crosslinked hydrogels (e.g. polyacrylamide, calcium alginate) or super absorbent polymer networks, the fundamental problem being that the PEG and gel networks are only bound by weak physical interactions, resulting in insufficient encapsulation robustness. In long-term use, high temperature or liquid impregnation environments, PEG molecules are very susceptible to leaching out of network pores by diffusion, resulting in rapid decay of function. More critical is that, in order to maintain the shape stability of the carrier network itself, a rigid structure with high crosslinking degree may be adopted, and the movement and the regular arrangement of the embedded PEG chain segments are severely limited, so that the crystallization capability of the embedded PEG chain segments is significantly inhibited, the actual measured phase change enthalpy value of the composite material is far lower than the theoretical value of PEG, and a large amount of heat storage capability is wasted. For example, liu et al （Water retention and heat storage characteristics of phase change hydrogel in cooling pavement[J]. Construction and Building Materials, 2024, 448: 138267.） absorbed PEG solution into Super Absorbent Polymer (SAP) network to form Phase Change Hydrogel (PCH), while possessing certain water retention property, saturated water absorption rate reaches 44.1%, but its internal rigid network severely limits PEG segment movement, resulting in crystallization enthalpy of only 12.07J/g, far below theoretical value, weak cold cycle heat storage capacity, revealing the double dilemma of "poor encapsulation" and "low phase change enthalpy" of physical blending mode. Strong chemical cross-linking strategy another strategy turns to building dense network tethered PEG based on permanent covalent or strong ionic coordination bonds for enhanced encapsulation. The strategy improves mechanical strength by forming a static, irreversible network structure, which also has a number of drawbacks. Firstly, too dense and irreversible cross-linked network also forms physical confinement to PEG crystallization, and the risk of lowering phase change enthalpy value exists, secondly, the strategy often improves certain mechanical properties such as tensile property, simultaneously causes unbalance and embrittlement of comprehensive mechanical properties of materials, lacks self-repairing capability after damage, and influences service life and reliability. For example, liu et al （Zn2+-Coordinated Phase Change Hydrogels with Enhanced Mechanical Properties and Quadruple Responsivity for Sensing[J]. Polymer, 2025: 129504.） prepa