Preparation And Application Of Bifunctional Hindered Amine Additives

At present,there are many kinds of commercial plastic additives,such as flame retardants,antioxidants,light stabilizers and so on.People can make up the deficiency of different additives in application by compounding,bring into play the synergy among additives,which can improve the comprehensive properties of polymer products.But the cost of compound is high,and the antagonism is easy to occur,which leads to the deterioration of performance.Therefore,the development of flame retardant,UV absorption,light stability and other functions of additives has gradually become a research hotspot.Among many light stabilizers,hindered amine light stabilizers have become the most widely used class of light stabilizers due to their advantages of high efficiency and low cost.Based on the structural innovation of piperazine derivatives,this paper uses melamine chloride and N-butyl-2,2,6,6-tetramethyl-4-piperidine as the starting material,three novel bifunctional hindered amine auxiliaries(TF-1,TF-2,TF-3)were designed and synthesized from cyanuric chloride and n-butyl-2,2,6,6-tetramethyl-4-piperidinamine,and the produces are used for the anti-aging application of PP,PE,ABS and other polymer materials.The specific findings are as follows:(1)A novel NOR-type dual-functional promoter TF-1 with flame retardancy and photostability is constructed by introducing cyclohexyl(-NOR)units into the hindered amine derivatives containing piperidine amine.The results flame retardant experiments show that the limiting oxygen index of PE film and PP spline with TF-1 is higher than that of blank PE film and PP spline.The photoaging test show that the tensile strength and elongation at break of PE films and PP splines with low doping content TF-1(0.1%,0.3%,0.5%)are much higher than that of blank samples under different aging time,indicating that the anti-aging ability of PE film and PP spline is significantly better than that of blank sample.In ABS samples,the comparison of yellowing degree(color difference value)further indicates that TF-1 sample has excellent anti-aging ability.In addition,the macro and micro morphology of PE film and PP spline also show that TF-1 had good anti-aging and migration resistance.Therefore,TF-1 has good flame retardancy and anti-aging properties.(2)By modifying piperazine derivatives with resorcinol,the intramolecular hydrogen bonds are constructed to endow them UV absorption properties,and the intermediate hydroxyl groups in the structure are etherified by chlorhexane,a new bifunctional promoter TF-2 with both UV absorption and photostability is obtained.Its structure is characterized by ~1H NMR,MS and FTIR.Thermogravimetric analysis show that TF-2 have good thermal stability,and the mass loss of TF-2 is less than 1%within 380°C.The anti-aging properties of PE film are compared with commercial UV-1577,the effect of TF-2(0.1%,0.3%,0.5%)is better than that of the blank and UV-1577,but the anti-aging effect of TF-2 is similar to that of UV-1577 in PP and ABS samples,and better than the blank sample.In addition,the surface morphology of PE film and PP spline show that TF-2 had better migration resistance than UV-1577 and better compatibility with the material.Therefore,TF-2 has excellent anti-aging properties,especially in the decorative thin materials have potential application value.(3)In order to improve the content of piperidine amine(light stable functional group),intramolecular hydrogen bond and tetramethylpiperidine alcohol are introduced into the structure of piperazine derivatives which designed and synthesized TF-3,a novel bifunctional adjuvant modified by piperidine with UV absorption and photostability.The UV spectra of TF-3 showed that TF-3 have UV absorption properties,and the maximum molar extinction coefficient is5.61×10~4 L/mol·cm.The results of mechanical properties test and color contrast study show that the aging resistance of PE film,PP spline and ABS samples with low content of TF-3(0.1%,0.3%,0.5%)is better than that of blank samples at different aging time.At the same time,TF-3 is not precipitated in the samples by the macro and micro morphology,which indicate that TF-3 have good material compatibility.Therefore,TF-3 has good anti-aging and Migration Resistance.