Research On Mechanical Properties Of Luffa Sponge As Sofa Filling Material

Luffa sponge(LS)is a kind of natural plant fiber material with rich resources,green and environmentally friendly.It is of great significance to develop a green economy by using LS to partially or completely replace sponge materials as a new environmental protection cushion material.This paper took the LS column as the main research object,and used the mechanical property test to study the effect of bearing direction,diameter,column height and two physical treatments of the LS column to its indentation hardness,support factor,deformation recovery performance and compression set.The results provided a theoretical research basis for LS as sofa cushion material.The durability test is used to simulate the partical durability of the LS sofa cushion under long-term use.The method of combining body pressure distribution test and subjective evaluation was used to explore the comfort of the LS sofa cushion.The main research results are as follows:(1)The bearing directions of the two density LS all have an effect on the four mechanical property inspection indexes,and the LS's bearing directions have different performances for different mechanical performance inspection indexes.The diameter of the LS only affects its indentation hardness,and the indentation hardness has a linear relationship with the diameter of the LS column.The indentation hardness of the high-density LS with a diameter of 50 mm is closer to that of the two commonly used sponges on sofa indentation hardness.The height of the column of LS affects its indentation hardness,deformation recovery performance and compression set.The indentation hardness of the high-density LS column with a height of 50 mm is closer to that of sofa sponges.Deformation recovery performance and compression set are all linearly related to the height of the LS column.After comprehensive consideration,a longitudinally loaded high-density LS column with a diameter of about 50 mm and a height of 50 mm is selected as the sofa cushion filling material.(2)The indentation hardness of the high-density LS column treated by the wet method is closer to the two sponges commonly used in sofas.The support factor of the two physically treated highdensity LS are higher than those of the two sponges.The improvement effect of compression method on the deformation recovery performance and compression set of LS is not as good as the wet metho d.These two indexes of the LS column treated by the wet method are closer to the sponge.(3)As the number of loading in the durability test increases,the cushion height of the LS cushion sample gradually decreases.During the durability test,the cushion height of the LS seat cushion sample has decreased by 6.46mm;as the number of loading increases,both the compression amount a and the compression amount c show a tendency to increase rapidly and then decrease slowly.The turning point occurs between the second and third stages of the durability test.During the test,the compression amount a changed by 10.68 mm,and the compression amount c changed by 8.30 mm.The cushion material of the LS sofa seat cushion has no obvious collapse and damage during the durability test.The results show that,under the simulation of the long-term effect of the 90 th percentile human body weight,the LS sofa cushion has a certain durability.(4)The results of the body pressure test show that the comfort of the ordinary sponge sofa cushion is better,and the stability of the LS sofa cushion is better.In terms of subjective evaluation,the LS sofa cushion has a stable sitting posture,with better comfort around the ischium,hips,medial and lateral thighs,and front end,while the ordinary sponge sofa cushion has better hip depression,softness,and elasticity.In addition,the subjects think the difference between the two is not much.Therefore,the comfort of the LS sofa cushion can be comparable to the ordinary sponge sofa to a certain extent.