Development　of　bio-based　hydrogels　with　good　mechanical　properties　is　of　great　importance　for　their　excellent　biocompatibility　and　biodegradability.　In　this　paper,　chitosan　(CS)　based　double　network　(DN)　hydrogel　was　prepared　by　dissolving　CS　in　AlCl3.6H(2)O　aqueous　solution　instead　of　acetic　acid　solution.　After　dissolving　acrylic　amide　(AM),　acrylic　acid　(AA),　N,　N＇-methylenebisacrylamide　and　2-hydroxy-4＇(2-hydoxyethoxy)-2-methylpropiophenone　were　added　into　the　CS/Al3+　solution　and　the　CS/PAMAA-Al3+　DN　hydrogel　was　prepared　by　UV　polymerization.　The　hybrid　physical　and　chemical　crosslinked　network　hydrogels　were　prepared.　The　tensile　and　compression　properties　of　CS/PAMAA-Al3+　DN　hydrogel　were　studied.　The　results　showed　that　the　CS/PAMAA-Al3+　DN　hydrogels　have　high　toughness,　stretch-ability,　and　excellent　shape　recovery　properties.　The　CS/PAMAA-Al3+　DN　hydrogel　could　show　the　tensile　strength　of　0.54　MPa　and　elongation　at　break　of　2203.7%.　These　properties　arise　from　the　dynamic　ionic　interaction　between　Al3+　and　CS/PAMAA　macromolecular　chains.　(C)　2017　Elsevier　Ltd.　All　rights　reserved.