Study On The Influence Of Gelatin Protein Retarder On The Properties Of Phosphorus Building Gypsu

Phosphogypsum,as a green and energy-saving building material,has been highly praised internationally for its advantages of light weight,small deformation,low production energy consumption,and harmlessness to the human body.It is widely used in the field of construction.However,as a building material,phosphogypsum has the defect of short setting time.In production application,phosphorous building gypsum will set and harden rapidly,its setting time is only 10 to 20 minutes,and its operable time is only 5 to 10 minutes.Can not meet the construction needs of building materials.Therefore,it is often adopted to prolong the setting time by adding retarder.In this subject,through the experimental comparison of bone glue protein with citric acid and sodium tripolyphosphate,the experimental effects of different retarders are evaluated from the two dimensions of setting time and physical strength as experimental standards.The results show that the bone glue protein retarder has a better retarding effect than citric acid and sodium tripolyphosphate at the same dosage.When the dosage is 0.3%,the final setting time of phosphogypsum mixed with citric acid,sodium tripolyphosphate and bone glue protein are 58 min,32 min and 87.5 min respectively,and the loss rates of flexural strength are 72.7%and 50.6%respectively,50.8%,and compressive strength loss rates were 59.8%,41.2%,and 41.3%,respectively.Therefore,bone glue protein can effectively prolong the setting time of phosphogypsum under the premise that the influence on the strength of phosphogypsum is relatively small.The effects of adding three retarders on the three aspects of liquid phase supersaturation,hydration rate and hydration temperature during the hydration process of phosphorus building gypsum were subsequently explored.At the same time,by observing the pore structure and crystal scanning electron microscope photos of the hardened phosphorus building plaster,the influence information of the three retarders on the crystal morphology and the pore structure of the hardened phosphorus building plaster was obtained.By comparing the crystal morphology of phosphogypsum with the same content of three retarders,the reason why the addition of retarders leads to the decrease of the macroscopic mechanical properties of gypsum is explained.The results of XPS test supported the retarding mechanism of the three retarders from the microcosmic point of view.Combining with various test results,the retarding mechanism of different retarders is expounded.Combined with the related research work on composite material reinforcing agent,by adding reinforcing agent to phosphorus building gypsum,the macroscopic mechanical properties of phosphorus building gypsum hardened body are improved.Graphene,g-C₃N₄,and graphite were selected as reinforcing agents for experimental comparison.By testing the macroscopic mechanical properties of phosphogypsum with reinforcing agents,the experimental effects of three reinforcing agents were evaluated.The experimental results show that:compared to blank stone building stone,when Graphene doped by 0.20%,phosphorus stone building stone is completely dry.The compressive strength increased by 34.86%,when g-C₃N₄ doped by 0.15%,the tensile strength improved by 38.86%,when the graphite doped by 0.05%,the tensile strength increased by 35.77%.And explore the effect of three reinforcing agents on the setting time of phosphorus building gypsum.Comparing the scanning electron micrographs of the pore structure and crystal morphology of the phosphogypsum hardened body with the same dosage of the three reinforcing agents,the effects of the three reinforcing agents on the crystal growth and the most probable pore diameter of the hardened phosphorus building plaster were analyzed.Combined with the experimental data,the mechanism of enhancing the macroscopic mechanical properties of phosphogypsum by the reinforcing agent is proposed.