| With more and more strict requirements of environmental protection, in the manufactureof electronic, electrical appliances, information products, has been widely used in newlead-free soldering. New solder of high melting point, special requirements to increase thewelding speed and the increase of temperature and the surface mount technology is added, thenylon66（PA66）, poly p-phenylene terephthalate (PBT) heat resistance materials cannot meetthe requirements, needs to use the other high temperature resistant engineering plastic toreplace.Nylon46(PA46) is a kind of novel polyamides of high melting point and highcrystallinity, but due to its high content of amide groups，it has high moisture absorption,resistance greatly on its wet high temperature lead-free soldering properties, at the same time,Flame retardant properties of PA46is poor, these shortcomings make the PA46is limited inthe electronic electric appliances etc., need to be modified. In order to solve the problem ofhigh water absorbent material PA46, further improve the high temperature resistance,mechanical properties and flame retardant properties, this paper mainly research contents andresults are as follows:Firstly, low moisture and resistant wet lead-free soldering better performance PA46/PPOalloy was prepared by polyphenylene ether (PPO) and PA46melt blend. The effects ofcontents on PPO, SEBS-MAH on properties of PA46composites were studied. The resultsshow that the modified, can reduce the absorption rate of PA46by PPO and PA46blend,improve PA46resistance to wet lead-free soldering performance, reached260℃; but withthe increase of PPO content, the mechanical properties of PA46/PPO alloy would graduallyreduce; so when the addition content of PPO was10%was the best. The addition ofcompatibilizer SEBS-MAH can improve the compatibility of PA46/PPO alloy, improve thecomprehensive properties of the alloy. The mechanical properties of the PA46/PPO alloy isbetter, water absorption rate is reduced to2.32%, when the content of SEBS-MAH was2%.Second, PA46composite materials were prepared by adding alkali free long glass fiber （GF） into PA46/PPO alloy. The process for preparation of composite material, and theeffect of glass fiber content on the properties of composite materials was investigated. Theresults show that, with the increase of the concentration of GF, water absorption of PA46/PPOalloy decreased gradually, especially after GF added to20%, decreased water absorption isobvious, when the content of GF is30%and40%, the sample water absorption rate decreasedto1.79%and1.42%respectively. With increasing of GF, mechanical properties, thermaldeformation temperature and resistance to wet lead-free soldering performance is improvedobviously, when the glass fiber content is30%, the tensile strength reaches177.2MPa,flexural strength reached241.9MPa, the notched impact strength reached14.3KJ·m-2,hardness (shore D) reached83, thermal deformation temperature at282℃, resistant to wetlead-free soldering temperature reached290℃,10s.Third, Halogen-free flame retardant glass fiber reinforced PA46composites wasprepared by using PPO and microencapsulated red phosphorus (MRP). The effects ofcomponents ratios and contents of PPO/MRP on properties of flame retardant glass fiberreinforced PA46were studied. The results show that when the mass ratio of PPO/MRP was1:1, and total content was12%, vertical combustion performance (1.6mm) of the sample canreach UL94V-0level. When the content of MRP is6%, PPO and MRP formed a synergisticmixture ratio better, through the synergistic effect formed a relatively stable carbon layer,carbon residue rate is higher, and enhanced the flame retardant level; GWFI temperaturereached960℃/1.5mm, the oxygen index test also reached a maximum of37.2%, low waterabsorption to1.79%, resistant to wet lead-free soldering properties at280℃. |
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