Research On Preparation And Properties Of Low Water Absorbent Nylon 6 And Attapulaite Composites

Nylon 6 is the largest one among the current polyamide plastics.However,PA6 has the disadvantages of high water absorption.The attapulgite is a new natural one-dimensional nanomaterial,because it has a larger aspect ratio,so it is an ideal reinforcement material for the preparation of high-performance composites.In this paper,the effects of different nucleating agents,glass fibers and compatibilizer or metallic polyethylene on the water absorption properties of PA6/AT composites are studied.The structure and performance relationship of the material are investigated and the mechanism of water absorption is further explored.Therefore a low water absorbent PA6/AT composite is prepared.The effects of different nucleating agents on the composite materials.The results of water absorption experiments showed that both A and B nucleating agents can reduce the water absorption of the PA6/AT system,and the A nucleating agent is more effective.After the addition of A nucleating agent,the composites moisture absorption decreased by 33.3%,measured at pure water 25 ? after 170h,compared with neat PA6.The mechanical properties of the composites showed that the mechanical properties of the PA6/AT composites are increased by adding of A or B nucleating agents.Compared with neat PA6,the tensile and flexura strength of the composite was improved by 5.4%and 12.2%respectively after adding of the nucleating agent A.The results of DSC showed that both A and B nucleating agents can increase the crystallinity of PA6/AT composites.Nucleating agent A can significantly increase the crystallization rate of PA6/AT composite.The effect of glass fiber on composite materials.The glass fibers make the PA6/AT/A composites moisture absorption further reduced by 35.5%at the same environment compared with pure PA6.GF can significantly improve the mechanical properties of PA6/AT/A system,the tensile and flexura strength of the composite is improved by 21.6%and 41%respectively,compared with pure PA6.The results of FTIR test showed that can hydrogen bonds formed between the glass fiber and the PA6/AT matrix material.The effects of compatibilizer or metallic polyethylene on composites.The absorption rate of PA6/AT/GF system could be further reduced by the compatibilizer PP-g-MAH or metallic polyethylene.And it was showed that mPE was superior to PP-g-MAH in compatibilizing.By adding of mPE(3wt%),the composites moisture absorption decreased by 40%,measured at pure water 25 ? after 170h,compared with neat PA6.Meanwhile,the tensile and flexura strength of the composite was improved by 36.8%and 51.7%respectively,compared with neat PA6.The interface bonding was observed by SEM:with PP-g-MHA or mPE,the interfacial bonding between glass fiber and PA6/AT composites can be significantly enhanced.The reasons for the decrease of water absorption rate of PA6/AT/GF composites.Firstly,the surface of the attapulgite and the glass fiber are due to the presence of silicone hydroxyl groups,its strong polarity with amine groups and carbonyl groups on the amide group in the molecular structure of nylon 6 forms hydrogen bonds.Second,attapulgite and glass fiber due to the synergistic effect.Finally,the adhesive material added into the composite material increases the adhesion between the systems,reduces the interfacial tension and reduces the size of dispersed particles,thus forming a stable structure and reducing the water absorption rate.