For the purpose of studying the properties mixing with other polymers of(CEBR), CEBR mixed with BR,S-SBR,R-SBR had been studied in this paper. The ingredients of s had been designed and optimized. The properties such as tensile strength, length at break, tearing strength, rigidity of s had been further studied in detail in order to show the effects of the ingredients. Besides, S-PVC blended with CEBR had been studied systemically. CEBR was blended to improve the toughness and impact resistance in low temperature of S-PVC. The results showed that:Firstly, the relatively reasonable ingredients of CEBR were: CEBR 100, Carbon Black 50, Zinc oxide 4, Stearic acid 2, Antioxidant 1, Sulfur 1.5, Accelerator 1.5.Secondly, as CEBR and BR were in the same scale in s, the length at break reached 201% in max. And the tensile strength reached 12.9MPa, lower than CEBR’s. Thirdly, the properties of mixed rubbers (CEBR/S-SBR, CEBR/R-SBR) had been improved, higher than CEBR’s.At last, along with the increasing scale of CEBR, the properties of S-PVC blended with CEBR had been changed. The tensile strength was getting lower and the length at break and impact resistance in low temperature were getting higher. CEBR with high content of chlorine contributed more to these changes.
Post about "Mechanical properties"
films have the excellent performance, so they are widely used in many fields. Because of the progress of science and technology, nylon 6 films must have higher performance.In this study, High-relative viscosity nylon 6 were prepared by means of anionic polymerization as main material, formic acid was used as a solvent.The effect of temperature and relative viscosity were discussed on solution viscosity. The effects of relative viscosity、temperature、 and low-molecular-weight nylon 6 resin on properties of nylon 6 films were investigated. The results showed that nylon 6 solution viscosity was decreasing with the increasing of temperature. Under the same temperature, the solution viscosity was increasing with the raising of high-relative viscosity of nylon 6. properties of nylon 6 films, such as modulus、yield stress、peak load and breaking strength were increasing with the increasing of relative viscosity and temperature. The addition of and low-molecular-weight nylon 6 resin increase the tensile strength of nylon 6 films. The addition of CaCO3 decrease the breaking strength and tensile strength of nylon 6 films . Adding anhydrous calcium chloride to the solution to produce complex films of nylon 6. The tensile property of nylon 6 films were improved above three times. The properties of nylon 6 films restore efficiently through by water.
Study on the Properties of Excellent Heat Resistant Resin Modified by Polyhedral Oligomeric Silsesquioxane (POSS)
In this paper, the octa(aminophenyl)silsesquioxane (OAPS) were synthesized. Furthermore, a novel(PI) hybrid nanocomposite containing polyhedral oligomeric silsesquioxane ( ) with well defined had been prepared by copolymerization of octa(aminophenyl)silsesquioxane (OAPS), 4,4′-oxydianilinediamine(ODA), and 4,4′-carbonyldiphthalic anhydride (BTDA). as nano-particles was covalently attached to the polymer backbone successfully. The results showed that the properties and thermal stability of the PI/ composites were significantly improved. The glass transition temperature (Tg) and modulus at high temperature dramatically increased, owing to the significant increase of the cross-linking density and molecular reinforcing effects of POSS in the nanocomposite. Taking pyromellitic anhydride (PMDA) instead of BTDA, the thermal properties wasn’t improved.Heptamertic cyclopentyl Trisilanol (T7) was synthesized and Cyanat Ester Resin was modified by T7 to get a series of CE/T7 organic-inorganic materials with different content of T7. As a result, T7 was copolymerized with cyanate ester monomer. The result showed that the existence of T7 resulted in increased flexibility and thermal stability of CE resin, while the dielectric properties of the modified CE varied little.
Polypropylene has good overall performances, lower cost, the very broad scope of its application. But Polypropylene is brittle(especially at low temperature), thus modification of Polypropylene become inevitable trend.In the first of this paper, the preparation of nano St-MMA copolymer by emulsion polymerization were studied, then add theto the matrix Polypropylene by In Situ Bubble Stretch Method, so PP nanocomposites were prepared. The micro-structure of PP nanocomposites were tested by scanning electron microscope (SEM) , and the results showed that by the method, nano particles were dispersed within a certain distance to bubble; the structure of PP nanocomposites were tested by X-ray diffraction, and the results showed that as a result of adding nanoparticles to the matrix, theβ-PP was generated in the matrix PP. Meanwhile, the samples that were prepared were injected into variety of spline, and were tested in properties. The results showed that when the loading of nano particles was 2 percent, the mechanical properties of PP nanocomposites were optimum, compared with pure PP, the notched impact strength increased 103 percent, and the tensile strength increased 22 percent, and flexural strength increased 9.6 percent.In order to compare the effect in modification to PP by nano St-MMA copolymer with the effect in modification to PP by nano Styrene Butadiene Rudder(SBR), PP/ composites materials were also prepared by method. The micro-structure of materials were tested by scanning electron microscope, and the results showed that with the tension of bubble, the nano particles around bubble have been achieved nano dispersed, and we found that the size of nano particles were different from each other as a result of distance to bubble; If adding different capacity to PP, the size of the nano particles by dispersed is different. The structure of PP nanocomposites were tested by X-ray diffraction, and the results showedthat as a result of adding nano SBR to the matrix, theβ-PP was generated in the matrix PP, so that the mechanical properties of composites materials had improved. The mechanical properties of test results showed that when the loading of nano particles was 7 percent, compared with pure PP, the notched impact strength increased 78.6 percent, and when the loading of nano particles was 3 percent, the tensile strength increased 29.8 percent, and flexural strength increased 14 percent, and the elongation at break increased 67 percent.
Acrylic resin is a group of related thermoplastic or thermosetting plastic substances derived from acrylic acid, methacrylic acid or other related vinyl compounds. Acrylic resin has some advantages, such as good glossiness, weather-resistant, chemical resistance and stabilization;is provided with non-contamination, nontoxicity, non-skin irritation, and low price and safety of production. But also has some disadvantages, such as high film forming temperature, low hardness,poor anti-after tack, poor water-resistant, low adhesion, etc. So the high performance acrylate polymer resin which can overcome those disadvantages will become research hotspot at present.In this paper, the waterborne acyrlic resin could be prepared by with acrylate monomers, and make preliminary discussion on synthesis techniques, and then, in order to improve the performance and enhance synthetic properties of copolymer, glycidyl acrylate ester of tertary carboxylic acid (E-6) and polyether acrylate ester (T550) which has high adhesion and low viscosity could be used for modifying .On the synthesis of anion ,many factors such as different initiator, reaction temperature,hydroxy and acid number on the polymerization process and product properties were discussed. The results showed that the anion could be favorably prepared and the conversion rate of monomers is greater than 98% when the reaction temperature is 130℃, the hydroxy number is 90 mgKOH/g and the acid number is 60 mgKOH/g. Meanwhile, the hardness of film is 3H and the adhesion strength is level 2.Besides, uniform Newton single-phase epoxy-organic silicone-acrylic resin was obtained by the copolymerization of acrylate copolymer which was carried out in ethanol using azobisisobutyronitrile(AIBN) as initiator, through radical polymerization of acryloyl silicone and acrylate monomer, and ring-opening reactions of epoxy828 and carboxyl . The stability, hardness, resistance to water and adhesion properties of the resin film was studied. The resin had good heat storage stability and pigment wettability. Epoxy-organic silicone-acrylic resin had a high glossiness, hardness and fullness, strong glass adhesion, good tolerance boiled and transparency.
Ni-coated carbon nanotubes（Ni-CCNTs）/AM60 composites and Ni-CCNTs/Mg-1 Zn-0.25Mn-xAl（0,1,3,5,8,10）composites were fabricated by stirring casting method under the protection of Ar.Theproperties of the composites which were under the state of as-cast and high temperature were tested.The was investigated with optical microscopy and tested by x-ray diffraction.The fractography characteristics of the composites were observed by scanning electron microscopy（SEM） and energy spectrum analysis（EDS）.The effect rules of room-temperature properties and elevated temperature properties of composites when enhancing the mass fraction of Ni-coated CNTs addition were investigated emphatically. At the same time, the change of was studied.The results showed that: the addition of Ni-coated CNTs could significantly enha- nce the properties of Ni-CCNTs/AM60 composites, the rules of which were always enhancing, then reaching the maximum, and dropping at last.Under the state of as-cast, when the addition of Ni-coated CNTs was 1.0wt%, the tensile strength, micro- hardness and the ductility reached the maximum,while the addition of Ni-coated CNTs were 1.2wt%, the elastic modulus reached the peak value respectively.Under the state of high temperature, the tensile strength declined remarkably, and the ductility enhanced. When the addition of Ni-coated CNTs were 1.2wt% and 0.8%, the tensile strength and the ductility all reached the maximum, which is 34.90% and 76.73% more than the value of the matrix respectively. Ni-coated CNTs could not only refine the grains of the composites, but also overlap the grains and bear the load of resistance to deformation. The fracture mode of composites mainly consisted of the dimple and the tear edge, which showed the feature of gliding fracture. When the addition of Ni-coated CNTs and Zn was 1.0%, At ordinary temperature, the tensile strength of the Ni-CCNTs/Mg -1Zn-xAl composites increased with the increase of the content of Al first, then reaching the maximum, and dropping at last, but the microhardness increased all the time. At high temperature the rule of tensile strength to the aluminum addition are similar to that of room-temperature, while the ductility declined all the time.With the increase of Al content, the Initial Phaseα-Mg declined, while the strengthening phase Al12Mg17 incr- eased and distributed more continuously, and also, the grain size decreeases obviously.
Research and development of Poplar-based oriented strandboard (OSB) will stimulate the effective and efficient uses of fast-growing poplar wood, the development of value-added OSB products and protection technology of wood-based panels as well. In order to develop polar OSB with decay and mold-resistant ability, seven preservatives, being Borate, Plygurad (PA), CuAz, naphthenate, TBQ, MA and MB, were selected and added at different levels to the three resin systems (UF, PF, MDI) to evaluate their effects on the properties of resins, the boardproperties and board fungi-resistant ability of poplar OSB as well. The leachability of preservatives were also determined by atomic absorption spectroscopy (AAS ) for MDI bonded OSB.The research results showed that:(1) additions did affect the properties of resins more or less. Both Borate and PA had very little influences on the pH of PF resin, but Borate addition increased the contact angle and velocity while PA acted in another way. Both them decreased the curing time of PF resin. The addition of MA , MB and PA decreased the contact angle of UF resin and affected the pH little, but MA and MB decreased the velocity and increased the curing time of UF resin.(2) treated with Borate had not only had excellent properties, but also performed outstanding at the decay-resistant test at the lowest addition level of 0.5%; boards treated with PA and naphthenate presented satisfied decay-resistant performance only at high addition level while the boards treated with lab-made CuAz had no improved decay-resistant performance though their properties were satisfied;(3) Borate and TBQ with high addition level were suggested to produce MDI bonded high performance fungi-resistant poplar OSB, while the middle and high addition level of PA showed good mold-resistant ability and naphthenate was a good choice to produce decay-resistant MDI bonded OSB products.(4) The 1% content level of MA and the 0.75% loading level of MB were suggested to adopted to produce UF bonded mold-resistant poplar OSB, for their both excellent mechanical properties, their minor effects on UF resin and their outstanding mold-resistant performance;(5) The fitting curve of long-term and short term mold-resistant efficacy determined that there was a good relationship between them.
Research on Aluminum Matrix Composites Synthesized by Direct Melt Reaction under High Intensity Ultrasonic
Aluminum matrix composites reinforced by Al3Zr and Al2O3 particles have been synthesized successfully by direct melt reaction method under high intensity ultrasonic from A356-Zr（CO3）2, A356-K2ZrF6 and Al-Zr（CO3）2 systems, respectively. With the helps of modern analysis methods, such as SEM, XRD, EPMA and so on, the phase compositions, microstructures,properties of the composites and morphologies, distributions of the in-situ particles in matrix are investigated, and the dynamics and the mechanism of in-situ ultrasonic chemistry reactions are discussed.The results indicate that the in situ chemical reactions for A356-Zr（CO3）2 and A356-K2ZrF6 systems are speeded with the high-energy ultrasonic field introduced into the aluminum melt, volume fraction is improved, and the reaction time reduced. The in situ particles are uniformly distributed in the aluminum matrix without machine whisking. The microstructures of the composites are optimized, the grains are refined, the Si phase is grain shape, and the properties increased. The applications of the composites in industry are promoted. These are due to the cavitation effects, acoustic-streaming effects, effects and the thermal effects of the high-energy ultrasonic field. In addition, the effects of the degassing and deslagging of the ultrasonic in the melt are contributed to the properties of the composites.The results of the XRD, SEM and EPMA analysis indicate that the particles synthesized from the A356-Zr（CO3）2 system with ultrasonic treated are Al2O3 and Al3Zr, which are uniformly distributed in the matrix, the size is about 0.5-1.5μm. The particles synthesized from the A356-K2ZrF6 system treated by ultrasonic field are Al3Zr, the size is about 1-3μm, and well distributed in the matrix. The particle and the interface are combined well. The SEM and XRD of the water-quench samples results indicate that the in-situ melt reaction mechanism for the A356-Zr（CO3）2 system with ultrasonic assistance is reaction-cracking-diffusion.The mechanical properties test results show that the tensile strength and the elongation of the as-prepared composites are obviously increased with the increase of ultrasonic power. For the A356-Zr（CO3）2 system, when ultrasonic power is 1.2kW, the tensile intensity of composites is higher by nearly 14.94% than that of without treatment, reached 402.31MPa. For the A356-K2ZrF6 system, the tensile intensity is reached 397.6MPa. The results of the analysis of the tensile fracture morphology indicate that the tensile fracture form is visible dimple fracture character. The strength mechanisms of the as-prepared are Orowan strength, fine-grained strength, solution strength and dislocation strength.
The PA1010-based nanos containing different surface-modified nano-SiO2 were prepared by melt blending method and in-situ Polymerization. The nylon 6 /nano- SiO2 s were prepared by in-situ polymerization. The properties of nano s were investigated in detail. The mechanisms of reaction between the different surface-modified nano-SiO2 and the nylon matrix were presumed and discussed, and the subsequent dispersing behavior of silica in nylon matrix was also characterized. Furthermore, the microstructure, crystallization, melting behaviors as well as thermal stability of the composites prepared by melt blending were systematically studied. At the same time, the effect of diferent surface-modified nano-SiO2 on the structure and properties of composites was also elucidated. The main results are summarized as follows:1. For the nano- SiO2 / composites prepared by melt blending, the results of testing showed that the addition of reactable nano-SiO2 （RNS） could reinforce the tensile strength, impact strength,break elongation and Yong’s modulus of nanocomposites. could improve the prorerties and had good effects on the reinforcement and toughening of the composites. The incorporation of dispersible nano-SiO2 （DNS） could increase the notched impact strength and break elongation of nanocomposites in the case of holding the Yong’s modulus of material; but would produce a negative influence on the tensile property of nanocomposites. For composites prepared by in-situ polymerazition, the addition of nano-SiO2 （whether RNS or DNS） could enhance the toughness and stiffness of composites, but the change of material tensile strength was not obvious.2. In order to farther analyse more deeply the interaction between different surface-modified nano-SiO2 and PA1010 matrix during the preparation of nanocomposites, the extraction treatment of nanocomposites was used, and extraction products were investigated by Fourier-transform infrared spectroscopy. The results showed that there was a strong interaction at the interface of RNS and PA1010 matrix, which promoted the formation of interface structure based on hydrogen bonding and covalent bonding. The interfacial interaction of DNS and PA1010 matrix is not very strong, which was connected each other only by few hydrogen bonding and intertwist of chains segments. When mechanical properties of RNS / PA1010 and DNS / PA1010 nanocomposites are compared, is found that different surface structure of nanoparticles would produce different influences on the mechanical properties of nanocomposites. In addition, based on the result of TGA the addition of nano-SiO2 could enhance the thermal stability of composites, but the effect of RNS on the thermal stability of material was more than that of DNS. The results showed that thermal properties of nanocomposites were closely correlated with the different surface structure of nano-SiO2.3. Melt and of DNS / PA1010 and RNS / PA1010 nano-composites prepared by melt blending were also investigated. The results showed that the addition of DNS and RNS had the different effect on the melt and of the composites. The addition of RNS increased the melt temperature and decreased the crystallization temperature of nanocomposites, promoted the crystallization of PA1010. At the same time the RNS increased the crystallinity of PA1010. While as a nucleating agent, DNS reduced the melt tempreature and increased the crystallization tempreature of composites. But it made the crystallinity of nanocomposites decreased a little. In the study of crystallization structure of nanocomposites, it was found that the addition of RNS and DNS did not change the crystal form of nylon 1010.4. The microstructure of nano-SiO2 / composites prepared by in-situ polymerization was characterized by scanning electron microscopy （SEM）, X-ray Diffraction （XRD） and Differential scanning calorimetry （DSC）. The results indicated that RNS and DNS could disperse rather well in nylon matrix. The addition of RNS and DNS changed the crystal form, hindered the formation of theγ-crystalline of nylon 1010. Nano-SiO2 made the melt temperature of increased 45 oC and the crystallization temperature increased 58 oC. These indicated that the filling of SiO2 acted as the heterogeneous nucleation spot of the crystallizing induced and made crystallizing process easier at higher temperature. At the same time, it is found that the effect of the nano-SiO2 added by in-situ polymerization on the melt and of nylon1010 was much more than that of it added by melt blending.5. The MC PA6 / nano-SiO2 composites were prepared by in-situ polymerization and their properties were investigated. The results showed that nano-SiO2 had little influence on the polymerization ofε-caprolactam when the load of nano-SiO2 was low. The strong interaction between nano-silica and caprolactam/sodium- caprolactam （hydrogen bonds and chemical bonds） accelerated the homogeneous dispersion of silica in the medium. Sequentially, this strong interaction made the tensile and impact strength increased, which indicated that in-situ surface-modified nano-SiO2 not only could strengthen but also toughen the nylon matrix. The results of XRD indicated that both MC nylon 6 and its RNS and DNS nanocomposites showed a typicalαcrystalline form diffraction peak. This meaned nano-SiO2 did not change the crystal modality of nylon 6. The TGA results showed that nano-SiO2 increased thermal stability of composites and the effect of RNS was much more than that of DNS, which were closely correlated with the different surface structure of nano-SiO2.
The ZA27-Mn,ZA27-Si and ZA27-Mn-Si alloys are prepared fromby adding Mn and Si in the form of Al-10%Mn and Al-7%Si. The solidification microstructures, the morphologies and distributions of the resultant phases are investigated by using Optical Microscope (OM), Scanning Electron Microscope(SEM), Electron Probe Microanalyzer (EPMA) and other modern equipments. The properties, friction wear properties and properties of after adding Mn and Si are tested, and the mechanisms are discussed.The results of microstructure of after adding Mn and Si indicate that the element Mn main exist in ZA27 alloy in the form of rich-Mn phase, the optimization amount of Mn is 0.4wt%, the crystal grains are well fined, the precipitated phases are distributed uniformly in the matrix alloy. The morphologies of the Si phase added into the ZA27 alloy in the form of Al-7%Si are particle-shape. When the addition amount of Si is 1.0wt.%, the Si phase is in near ball-shape distributed in the matrix. With the additions of 0.4wt%Mn and 1.0wt%Si, the dendrite crystals are turned into puncheon crystals, and the the precipitated phases are fine in the continuities. With the increase of the ultrasonic power, the dendrite crystals are turn into puncheon crystal, Si particles are fined and distributed more uniformly in the matrix.The properties tests show that the hardness and tensile strength of the ZA27 alloy with adding Mn and Si increase. When adding 0.4wt%Mn, the hardness, tensile strength and elongation are 126.8HB, 410.32MPa and 4.01%, increased by 9.03%, 8.76% and 22.26% than that of the ZA27 alloy, respectivelity. When the content of Si reach 1.0wt%, the hardness, tensile strength and elongation are 124.9HB, 412.89MPa and3.49%, increase 7.40%, 9.44% and 6.41%, respectivelity. The properties are improved under different power of the ultrasonic field with 0.4wt%Mn and 1.0wt% Si .The tensile strength, elongation and hardness are all improved. When the power of the ultrasonic field is 1.2kw, tensile strength and elongation are increased by 17.23% and 24.39% compared with the matrix alloy, and by 6.17% and 9.38% compared with adding 0.4wt%Mn and 1.0wt% Si. The change of the hardness is small.The analyse of the SEM of the tensile fracture surface show that the fracture mechanisms are mixed by fracture-the plastic fracture and the brittle fracture.Oil sliding wear tests at room temperature show that the wear resistance of the alloy with Mn adding is superior to that of its matrix alloy. When adding 0.4wt%Mn, the wear weight loss is 0.46mg under 600N load, reduced by 44.58% to the matrix alloy, the friction coefficient is 0.028, reduced by 17.65%, the stability is increased. After adding Si, the resistance of the alloy are improved.When adding 1.0wt%Si into the alloy, the wear weight loss is 0.45mg under 600N load, reduced 45.78% to the matrix alloy, friction coefficient is 0.026, reduced by 23.53% to the matrix alloy, the stability is improved. With the increasing of load, the wear loss weight, friction coefficient are all increased, and the stability decreased. Adding with 0.4wt%Mn and 1.0wt% Si, under different power of the ultrasonic field, with the increasing of the power, the wear loss weigh are reduced, and the friction coefficient reduced, the stability enhanced.The analyse of the wear surface indicates that the wear mechanism is abrasion wear under the oil sliding and low loads conditions. With the loads increasing, the abrasion wear are weakened gradually, and adherence wear increased, in larger load, the wear mechanism is adherence wear and abrasion wear.The results of of alloy show that the liner expansibility and the thermal expansibility of ZA27 alloy are decreased with the adding of Mn. When adding 1.0wt%Si into the ZA27 alloy, the liner expansibility of the material decreased. Adding with 0.4wt%Mn and 1.0wt% Si, the liner expansibility diminish. The ultrasonic field minished the liner expansibility, but its influence is not great.