Preparation And Application Of Polycaprolactam-b-polyether Permanent Antistatic Agents

Due to the good antistatic effect,durable antistatic,water-washing resistance,free from humidity,excellent heat resistance,high mechanical properties and little influence on the properties of matrix,polycaprolactam-b-polyether copolymers permanent antistatic agents have become a research focus all of the world in recent years.However,a two-step method whichiscomplexandcostlyisusuallyusedforthepreparationof polycaprolactam-b-polyether copolymers permanent antistatic agents in China now.In this paper,polycaprolactam-b-polyether copolymers permanent antistatic agents were prepared via on one-step process by melt in-situ copolycondensation with caprolactam?CL?,polyethylene oxide?PEO? and polytetrahydrofuran?PTMG? as materials,which was a simple process.The preparation process of permanent antistatic agents was explored.The structure and properties of polycaprolactam-b-polyether copolymers were systematically analyzed.The application of polycaprolactam-b-polyether copolymers antistatic agents in permanent antistatic ABS was also studied.Firstly,polycaprolactam-b-polyether copolymers were successfully prepared by melt in-situ copolycondensation based on one-step process.The molecular weight of polycaprolactam prepolymers was regulated by adipic acid as end-capping agent,and the effect of molecular weight of polycaprolactam prepolymers on the copolymer was studied.The optimal esterification process parameters of polycaprolactam and polyether?PEO,PTMG?were studied by controlling variable method.The preference temperature of esterification reaction should be 230?.The time of esterification should be 3 h.The vacuum degree should be 200 Pa.The amount of Sb₂O₃ catalyst should be about 0.06wt%.The amount of antioxidant A should be chosen as antioxidant,which is about 2wt‰.The polyamide-b-polyether copolymers synthesized under these conditions have high viscosity,high conversion,light color,high transparency and stability.Secondly,the effects of soft/hard ratio,molecular weight of PEO and types of polyether?PEO,PTMG?on the structures and properties of polycaprolactam-b-polyether copolymers antistatic agents were studied.Different structures of caprolactam-b-polyether copolymers have good thermal stability below 300?,and can be processed under usual conditions.The ordersof magnitude ofsurfaceandvolume resistivity of polycaprolactam-b-polyether copolymers are between 7 and 9,which have permanent antistatic ability.With the increase of PEO contents,the antistatic performance of PEO-b-PA6 is improved.The antistatic performance of PEO-b-PA6 is improved with increasing molecular weight of PEO.As compared to PTMG-b-PA6,PEO-b-PA6 has stronger water absorption and better antistatic property.Polycaprolactam-b-polyether copolymers are a typical microphase separation structure.With the increase of soft/hard ratio,the phase separation of PEO-b-PA6 is more serious,and the tensile strength of PEO-b-PA6 copolymer decreases.However,the elongation at break of PEO-b-PA6copolymer increases initially and then decreases with increasing soft/hard ratio.With the decrease of PEO molecular weight,the phase separation of PEO-b-PA6 is not obvious,and the elongation at break and strength of PEO-b-PA6 decreases.The phase separation of PTMG is more serious than PEO-b-PA6,and its mechanical properties are slightly better.In addition,the elongation at break of polycaprolactam-b-polyether copolymers with different structures are between 690% and 1170%,and the toughness of polycaprolactam-b-polyether copolymers is good.Finally,the application of polyamide-b-polyether copolymers antistatic agents in ABS was studied.Polyamide-b-polyether copolymers antistatic agents exhibit three-dimensional network structure of fibrous or lamellar structure in ABS,which can result in conductive channel.The orders of magnitude surface and volume resistivity of antistatic ABS can be reduced by six to eight.With the addation of PEO-b-PA6?70/30? antistatic agent,ABS/PEO-b-PA6 blends are unwashable and nonpermanent,and the rest of the antistatic ABS are washable and permanent.The melting index of antistatic ABS blends is larger and processing fluidity is better.The tensile strength and bending strength of antistatic ABS are reduced,but the notched impact strength of some antistatic ABS is improved.