PET微粒增强聚丙烯酸正丁脂吸油树脂的制备及其性能研究(英文).doc

Preparation and properties of poly butyl acrylate oil-absorbing resins strengthened by polyethylene terephthalate particleAbstract:With butyl acrylate(BA) as monomers,polyvinyl alcohol(PVA) as dispersing agent,benzoyl peroxide(BPO) as initiator,prepared poly butyl acrylate high oil-absorbing resin by suspension polymerization.Researched the the influence of content of polyethylene terephthalate particle and treatment process on the oil absorption of resins and analyzed the crystallization properties and thermal properties through differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA).The results show that the addition of PET particles decreased the oil absorption rate and affect the crystallization properties and thermal properties of the resins.Besides, the heat treatment by twin screw extruder made the oil absorption of the resin decreased significantly and had a large effect on the crystallization properties of the resin.Keywords:PET particle,treatment, twin screw extruder,oil absorbency,crystallization properties,thermal properties.1.IntroductionWith rapid development of modern industry, the use and transportation of all kinds of oil have become an integral part of the production and life. The river and sea water pollution problems caused by oily organic compound and its sewage, waste liquid and all kinds of accidents such as the leakage of oil tankers and storage tank have become increasingly serious,of which the industrial waste water pollution account for 30% and the sea tanker leakage pollution account for 45%1,oil recovery and purification become a hot spot of research.Traditional oil absorption materials such as cotton, polypropylene and polyester nonwoven fabric can not meet the requirements of waste oil recycling and environmental management, research and development of high performance oil absorption materials is imperative.At present, the high oil absorption resin is a kind of new oil absorption material which has been widely researched,because of its large variety of oil absorption, high oil absorption, oil/water good selectivity and compression does not leak, thus has broad prospects for development.2,3Depending on the monomer, the reported high oil absorption resin can be divided into two basic categories:One kind is olefin resin,but the source of high carbon olefins is less;Another kind is acrylic resin, (meth) acrylate monomer for common, which has a rich source, so these products become the main research direction of domestic high oil absorption resin.Guojiang Yin used suspension polymerization to synthesize the low degree of crosslinking acrylic vinegar class oil-absorbing resin, oil absorption properties of the resin was investigated.Guorong Shan used suspension polymerization to synthesize single chemical crosslinked and physical and chemical compound crosslinked polyacrylate high oil-absorbing resin.Milan used acrylate monomers to synthesize fluffy granular high oil-absorbing resin inside which has micropores.Jang Jyongsik and Kim Beomseok synthesized styrene/acrylic acid-2-ethyl hexyl ester,styrene/acrylic twelve ester,styrene/methyl acrylic twelve ester and styrene/acrylic eighteen ester copolymer resin,studied and compared its structure and properties5,6.Ayman M.Atta and K.F.Arndt synthesized acrylate copolymer oil-absorbing resin7-10.However,the (meth) acrylate polymer is elastic and go soft under high temperature,especially when in contact with the organic solvent.All above will decline its strength and lost the use of value,so it is very meaningful to strengthen the resin.PET has has excellent stiffness properties, high strength and good chemical stability.Using PET as a reinforcing material of the (meth) acrylate resin to prepare a kind of high strength of oil-absorbing material is of great significance.This article embarks from the n-butyl acrylate,prepared poly butyl acrylate wrapped by PET particle and investigated its properties.2.Experimental2.1 Materials Butyl acrylate(BA)was purchased from Tianjin Guangfu Chemical Research Institute and used directly;Poly (vinyl alcohol) was purchased from Tianjin Chemical Reagent Co.,Ltd,purified by washing with deionized water before use;Benzoyl peroxide (BPO) was purchased from Shanghai Chemical Reagent Co.,Ltd.,a branch of China National Pharmaceutical Group Corp and used directly;Polyethylene terephthalate(PET) was purchased from Zhejiang Rongsheng chemical fiber group Co.,Ltd and its melting point is about 260;Trichloro ethylene was purchased from Tianjin Guangfu Chemical Research Institute and used directly.2.2 Synthesis of resin and the heat treatment First，quantitative deionized water and PVA（a total of 450 ml）were stirred in a 1000 ml three mouth flask,and then quantitative butyl acrylate and BPO(MBPO/Mmonomer = 0.5%) were stirred in a 250 ml beaker until a homogeneous solution were formed.Finally,the solution and quantitative PET particle were put into the 1000 ml three mouth flask and stirred to react at 85 for 3 h under a nitrogen atmosphere，and then the temperature was increased to 95 to make the system continue to react for 3 h，white copolymer was obtained after the product was washed and dried in vacuum oven at 60 for 72 h(mass fraction of PET in monomer feed ratio was assigned to 0,20,and 40 wt% and were marked as 3 #,7 #, 2 # sample in the test).Taking 2 # sample mixed with PET particles（Mresin/MPET=7/3）and set screw process conditions:zone 1:250,zone 2:260,zone 3:260,zone 4:260,zone 5:270,zone 6:270,melt pump:260,melt:260,frequency of mainframe:4.0 HZ,frequency of melt pump:25.4 HZ,current of mainframe:9.0 A.Extruded the mixture by twin screw extrude and marked as 5 # sample in the test.Besides,taking 3 # sample and PET extruded by twin screw extrude with the same conditions and marked as 6 #,4 # sample.The untreated PET was marked as 1 # sample in the test.2.3 Test analysis2.3.1 Oil absorbency A weight of 1 g each sample was placed in trichloroethylene for 24 h at room temperature until equilibrium was reached.The samples were weighed after removing excess oil.The absorbency, Q, was determined by weighing the swollen gel and calculated according to the following equation: Q= ( m1- m0 ) / m0 where m1 is weight of swollen gel and m2 is weight of sample.2.3.2 TGA analysis A NETZSCH STA409PC thermogravimetric analysis was used to characterize the thermal properties of the samples.All measurements were carried out under nitrogen atmosphere at a heating/cooling rate of 10/min and the temperature range from 20 to 30 DSC analysis A NETZSCH DSC 200F3 differential scanning calorimeter was used to characterize the crystallization properties of the samples.All measurements were carried out under nitrogen atmosphere at a heating/cooling rate of 10/min and the temperature range from 20 to 300.3.Results and discussion3.1 Effect of the content of PET particle on oil absorbencyOil absorbency versus time for untreated sample is shown in Fig.1.Obviously,the untreated poly butyl acrylate has the best oil absorption performance,however ,the oil absorption rate of poly butyl acrylate wrapped by PET particle decrease significantly.Also,PET particles hardly has oil absorption performance and occupy the free volume of the resin and reduce the contact area between the resin and oil molecules.For that reason,with the increase of the content of PET particle,the oil absorption rate of the resin decrease gradually.For the above samples extruded by twin screw extrude ,the test results are shown in Fig.2.As Fig.2 shows,for the resin extruded by twin screw extrude,the absorbency changes fewer with the increase of time.In addition,compared with the untreated samples the oil absorbency is very low and lost the high oil absorbency property.Fig.1 Variation of absorbency with absorptive time; the mass fraction of PET particle is as follows:(a)0 wt%,(b)20 wt%,(c)40 wt% and d for PET particleFig.2 Variation of absorbency with absorptive time;the mass fraction of PET particle is as follows:(a)0 wt%,(b)40 wt% and c for PET particle3.2 Effect of process on oil absorbency The heat treatment by twin screw extruder has a large effect on oil absorbency and the results are shown in Fig.3.It can be seen that the heat treatment by twin screw extruder made the oil absorption of the resin decreased significantly.It can be clearly seen that the samples dispersed in trichloroethylene and cannot form gel in the test process.This is due to the poor spinning performance of PBA and exist a certain degree of thermal degradation in the process of melt extrusion. Fig.3 Variation of absorbency with absorptive time ;a for the untreated PBA resin,b for the PBA resin extruded by twin screw extruder,c for the PET resin extruded by twin screw extruder,d for untreated PET resin3.3 Effect of the content of PET particle on crystallization properties In the process of application of the resin, it is necessary to consider its crystallization properties sometimes.In order to find out the effect of the content of PET particle on crystallization properties,DSC analysis was performed.The results analyzed by DSC are shown in Fig.4.For PET resin,there exist a crystallization peak and a melting peak in the heating process.The crystallization peak temperature is 136.8 and the melting peak temperature is 253.8.For PBA resin,there is only a crystallization peak at the temperature of 184.6.For PBA resin wrapped by PET particle,the crystallization is very weak in the heating process and there is a melting peak at a temperature of 254.3.In the process of cooling,it can be clearly seen that the PBA resin has no crystallization peak from Fig.4(b).Compared with PET resin,the crystallization peak temperature of PBA resin wrapped by PET particle is higher.In addition,the three kinds of sample exist a weak crystallization peak at a temperature of about 66.5 in the cooling process, it may be caused by macromolecular crystallization of side chain. （a） (b)Fig.4 DSC thermograms of resin wrapped by PET particle;(a)for heating thermograms,(b)for cooling thermograms;mass fraction of PET particle is labeled as follows:(3#) 0 wt%,(2#) 40 wt% and 1# for PET resin3.4 Effect of the content of PET particle on thermal properties In the process of application of the resin, it is necessary to consider its thermal properties sometimes.Thermal behavior of polymer can be evaluated with weight loss by thermogravimetric measurement.As shown in Fig.5(a),the initial decomposition temperature of PET is highest and it has excellent thermal stability.For PBA resin wrapped by PET particle and pure PBA resin,they have the same initial decomposition temperature because PBA degrade first in the process of thermal weight loss.As Fig.5(b) shows,PET resin has the highest temperature of the maximum mass loss rate. The PBA resin wrapped by PET particle and pure PBA resin have almost the same temperature of the maximum mass loss rate.However,for the PBA resin wrapped by PET particle,there exist two peaks in the DTG curves which shows that the thermo-gravimetric process of the PBA resin wrapped by PET particle can be divided into two stages:the first stage is the thermal decomposition process of PBA resin and the second stage is the thermal decomposition process of PET resin.In general,the addition of PET changed the thermal performance of the PBA resin and make its thermal decomposition process different from the pure PBA resin. （a） (b)Fig.5 TGA(a) and DTG(b) of resin wrapped by different content of PET particle3.5 Effect of process on crystallization properties The heat treatment by twin screw extruder changed the crystallization properties of the resin.The results analyzed by DSC are shown in Fig.6.Fig.6(a) shows that there are no obvious crystallization peaks in the heating process of PET resin extruded by twin screw extruder and it has a similar melting peak with untreated PET sample.It can be seen from Fig.6(b) that the PET resin extruded by twin screw extruder has a obvious crystallization peak in the cooling process.In fact,the PET resin has completed a crystallization process in the extrusion process and the chain segment of extruded PET is easier to arrange regularly.The extruded PBA resin wrapped by PET particle has no obvious crystallization peaks in the heating process because of the crystallization in the extrusion process,as shown in Fig.6(c).The heat treatment has a large effect on the resin wrapped by PET particle in the cooling process and the results are shown in Fig.6(d).It can be seen that the extruded resin has a obvious crystallization peak in the cooling process.What is more,PET has a strong crystallization capacity so that the resin wrapped by more PET particle has a obvious crystallization peak in the cooling process. （a） (b) (c) (d)Fig.6 DSC thermograms of resin;(a)and(c)for heating thermograms,(b)and(d)for cooling thermograms3.6 Effect of process on thermal properties The thermal properties of the treated resin has no obvious changes.As shown in Fig.7,the initial decomposition temperature and the temperature of the maximum mass loss rate is almost constant.For PBA resin wrapped by PET particle,with no changes in the initial decomposition temperature and temperature of the maximum mass loss rate. （a） (b) (c) (d) Fig.7 TGA(a)(c) and DTG(b)(d) of resin 4.Conclusions This article embarks from the n-butyl acrylate,prepared poly butyl acrylate wrapped by PET particle and investigated its properties.With the increase of the mass fraction of PET particle,the oil absorption rate of the resin decrease gradually.Because the PET particle occupy the free volume of the resin and reduce the contact area between the resin and oil molecules.However,the PET particle form a rigid skeleton inside the resin and improve the application performance.The addition of PET particle changes the crystallization properties and thermal properties.The thermo-gravimetric process of the PBA resin wrapped by PET particle can be divided into two stages and improve its thermal performance.The heat treatment by twin screw extruder has a large effect on oil absorbency.It make the oil absorption of the resin decreased significantly and the resin dispersed in trichloroethylene and cannot form gel.This is due to the poor spinning performance of PBA and exist a certain degree of thermal degradation in the process of melt extrusion.In addition,the heat treatment changes the crystallization properties of the resin and make it has no obvious crystallization in the heating process.In a certain range of temperature,the heat treatment has a great influence on the crystallization properties but little on thermal properties.References:1 XIAO Chang-fa, XU Nai-ku, AN Shu-lin, et al. Method of preparing oil absorbing fibers. US. 8110525(US12541918) P.2012-02-07.2 JI Shun-jun , DAI Wei-quan , DI Hai-sheng , et al. Study on high oil absorptive resin of copolymer of hydroxyethyl acrylate and (2-ethylhexyl