Effect Of Common Dispersant On The Properties Of Penicillin Residue/LDPE Composite And Mechanism Analysis

In order to eliminate the hidden troubles caused by the penicillin residue produced by mass production of penicillin,and at the same time make the best use of the rich sub-stances in penicillin residue,the use of penicillin residue to prepare composite materials was born.In this paper,penicillin slag powder is used as biological material,low-density polyethylene?LDPE?as matrix,attapulgite,light calcium carbonate and cyanobacteria powder as dispersant.The composite material is prepared by twin-screw extrusion granulation.Analysis of mechanical properties,to explore the optimal ratio,addition amount and particle size of penicillin residue powder and dispersant;analyze the changes of the absorption peak position and intensity of the composite material by infrared spectroscopy to characterize the changes of the functional groups of the reac-tants and products,thereby revealing Inner mechanism of chemical reaction between penicillin slag powder and LDPE to prepare composite materials;observation of the morphology of penicillin slag powder and its composite materials through scanning electron microscopy to discuss the dispersibility of the dispersant;through the embed-ding method experiment,setting topsoil and containing anaerobic A mixed soil control group of bacteria was used to study the weight loss rate of composite materials and to explore the degradation ability of composite materials.?1?By analyzing the dispersing effect of three dispersants including attapulgite,light calcium carbonate and cyanobacteria powder on penicillin residue powder and the compatibility effect on the composite material system,the experimental factors of the different mass ratios between penicillin residue powder and dispersant,the amount of mixed powder added and the sieve number of mixed powder particles were discussed.It can be obtained that,The mixture of attapulgite as dispersant and penicillin slag powder in proportion was combined with low density polyethylene?LDPE?to prepare the composite material with the optimal mechanical properties.The optimal conditions were:penicillin slag powder:attapulgite=1:2,adding 15%of the mixed powder,and the mixed powder particles were screened for 80 mesh.At this point,the tensile strength,bending strength,bending modulus and impact strength of the composite were 12.5Mpa,8.39Mpa,200Mpa and 57KJ/m²,respectively.?2?Through the analysis and study of the weight loss rate of the composite material by soil burial method,the composite material prepared with cyanobacteria powder as dispersant had the best degradation effect in the topsoil and the mixed soil with anaero-bic bacteria.After 240d,the weight loss rate of the composite material reached the maximum of 9.24%.?3?Infrared spectroscopy analysis shows that the penicillin residue powder shows a strong-OH characteristic peak at 3280cm^-1,1650-1440cm^-1is the stretching vibration peak of C=O in carboxylic acid,and 1420-1330cm^-1 is a symmetric carboxylate anion-The COO-extension vibration indicates that the penicillin bacterial residue powder is likely to contain carboxyl organic substances.In the infrared spectrum of PE-g-MAH,anhydride functional groups appeared at 1850cm^-1 and 1740cm^-1,and cyclic anhydride C-O-C appeared at around 1200cm^-1.In the infrared spectrum of the composite material,the characteristic absorption peaks corresponding to the carboxyl group,O-H and male-ic anhydride in the bacterial residue powder have been weakened or disappeared,which shows that the esterification reaction occurred during the preparation process.?4?It can be found intuitively by scanning electron microscope.Comparison of the three dispersants shows that attapulgite has the best dispersion of penicillin residue powder.