Study On The Surface Modified Chopped Fiber Reinforced Phosphorus Building Plaster

Phosphogypsum is a kind of solid waste with large storage,large discharge and serious environmental pollution.It solves the problem of comprehensive utilization of phosphogypsum.On the one hand,it can solve the environmental pollution caused by the massive accumulation of phosphogypsum,and on the other hand,it can promote phosphorus chemical industry.Sustainable development of the enterprise.The use of phosphogypsum to produce phosphorus building gypsum,and then to prepare various phosphorus building gypsum products,is an effective way to utilize phosphogypsum.The biggest problem in limiting this approach is that the strength of phosphorus building gypsum products produced by using phosphogypsum is much lower than that of natural gypsum products,and it is difficult to meet the requirements for use.In this thesis,the fluidity,setting time and hardening strength of the hardened building gypsum slurry of chopped basalt fiber,chopped glass fiber and chopped polypropylene fiber under different lengths and different volume were studied.The effects of compressive strength and water absorption were analyzed by SE M microscopic test and macroscopic test.The effect of hydrochloric acid etched basalt fiber on the performance of phosphorus building gypsum products was further studied.And get the following main conclusions:(1)Short-cut fiber has obvious influence on the working performance of phosphorus building gypsum: the blending of chopped basalt fiber and glass fiber,the fluidity of phosphate building gypsum has been greatly reduced,the setting time of pulp is shortened;the chopped polypropylene fiber to phosphorus building Gypsum paste fluidity and condensation time have less effect.(2)The effect of chopped polypropylene fiber on the working performance of phosphorus building gypsum is less than that of basalt fiber and glass fiber;chopped basalt fiber and chopped glass fiber are hydrophilic fiber,and the free water in the slurry is enriched toward the fiber distribution position.Phosphorus building gypsum net pulp has a relatively low free water content,which leads to a decrease in slurry workability;chopped polypropylene fibers are hydrophobic fibers,and free water in the slurry is concentrated toward the opposite position of the fiber distribution,and phosphorus building gypsum is free.The water ratio is constant,so the impact on the working performance of the slurry is small.(3)The effect of chopped fiber on the performance of phosphorous building gypsum hardened body is obvious: for short-cut basalt fiber and glass fiber,the length specification is 6mm,the volume content is 1.2%,the phosphorus building gypsum hard body is absolutely dry and folded.The compressive strength reaches the maximum value;for the chopped polypropylene fiber,the length specification is 9mm,and when the volume is 2.4%,the hardening resistance and compressive strength of the phosphorous building gypsum hardened body reaches the maximum;in the same length specification,fiber In the case of the amount of chopped fiber,the effect of the flexural strength and compressive strength of the phosphorous building gypsum hardened body is the best,the chopped basalt fiber is the best,the glass chopped glass fiber is the second,and the chopped polypropylene fiber is the worst;The water absorption rate of phosphorus building gypsum increases with the increase of fiber content.The influence of chopped fiber on the water absorption rate of phosphorus building gypsum is from small to large: chopped basalt fiber < chopped glass fiber < chopped polypropylene fiber.(4)The chopped fibers are randomly distributed in the chopped fiber-phosphorus building gypsum composite material,and the two ends are randomly distributed in three dimensions.In the chopped fiber-phosphorus building gypsum composite material,chopped fiber can play the role of delaying the occurrence and development of micro-cracks on the one hand,and can bridge the visible cracks on the other hand,and play the role of load,thereby improving the construction of phosphorus.Flexural strength;when the fibers appear in the composite material in a poor distribution state such as bunching,agglomeration,etc.,the strength of the composite material is adversely affected.(5)Short-cut basalt fiber treated by hydrochloric acid surface etching,the surface of the fiber reacts with hydrochloric acid,and the surface roughness of the fiber increases,thereby enhancing the mechanical locking force between the basalt fiber and the phosphorus building gypsum matrix.The etched chopped basalt fiber has a better reinforcing effect on the phosphorous building gypsum hardened body than the untreated chopped basalt fiber.The performance indexes of the chopped fiber-phosphorus building gypsum composites prepared in this paper are greatly improved compared with the phosphorus building gypsum,which can meet the actual use requirements in the construction process.At the same time,the paper discusses the mechanism of fiber-reinforced phosphorus building gypsum.The research has been carried out and the research conclusions obtained have certain research and reference value.