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1.
We study the changes in adhesive properties of poly(vinyl butyral) (PVB) sheets assigned for safety glass preparation. PVB sheets have been produced by various worldwide manufacturers by simple blending methods such as extrusion, thermo‐mechanical mixer processes, etc. Some samples were modified either by magnesium acetate or by oligo‐functional organic acid to either reduce the adhesion to glass or to increase it. Adhesive measurements were evaluated on the air side and the tin side of the laminated glass. The study deals with a recognition of causes of the PVB adhesion change as a function of adsorbed water content into the polymer matrix. Results describe the influence of hydroxyl group content and amount of added acid–base reactants for adhesion adjustment of every tested PVB sheet. It also describes typical adhesion fluctuation and specific adhesion bonding of PVB sheets to glass in particular conditions. The analysis evaluates the best and the worst blend combinations and their modification on the adhesion change. We focused on adhesion sensitivity to increasing water content and the amount of added adhesion modifier. This work also evaluated the critical range of water content that provides adhesion fluctuation. The evaluation of various types of PVB sheets was performed and the most stable adhesion adjustment was found. Obtained values and comparisons are very important for the PVB sheets industry and for industry dealing with lamination of laminated glasses. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

2.
The study is focused on windshield recycling process resulting in poly(vinyl butyral) (PVB) sheets with very low amout of remain glass particles. PVB sheets were obtained from worldwide manufacturer DuPont and then they were laminated by standard autoclaving process. One sample of PVB sheet was modified by multi‐functional organic acid in order to compare various levels of adhesion. Three‐stage technology was proposed for recycling PVB sheets. In the first‐stage laminated safety glass was mechanically cracked. In the second‐stage the adhesion reduction to minimal degree was followed by chemical‐physical assisted separation. It causes self‐release of the glass out of the PVB sheet. The third‐stage was mechanical peeling of the remaining glass from the PVB sheet which completed the recycling process. The optimal process conditions for the most effective delamination process were found. Delamination technology produces PVB sheet with minimal residual glass content (up to 300 ppm) and minimal change in PVB sheet properties. Described recycling technology is ecologically friendly (the effluent is fully recyclable as well) and could reduce the worldwide problem with windshield waste disposal. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39879.  相似文献   

3.
聚乙烯醇缩丁醛的合成新工艺   总被引:2,自引:0,他引:2  
通过对聚乙烯醇缩丁醛(PVB)的合成工艺进行改进,并在不加任何乳化剂的条件下,制得了完全粉末状的PVB产品;将其用于夹层安全玻璃的制备,则雾度值为0.41%,完全符合夹层安全玻璃的使用要求;并讨论了各因素对PVB产量的影响。实验结果表明,当m(PVA)∶m(正丁醛)∶V(HCl)=100 g∶56 g∶15 mL时,PVB的产量最高,其乙烯醇缩丁醛含量可达77.7%。  相似文献   

4.
《Ceramics International》2019,45(11):14073-14083
Nanoscale NixMg1-xAl2O4 spinel pigments were synthesized by a citric acid precursor combined with the gel-casting method. The microstructure, cation distribution and optical properties as a function of calcining temperature and nickel content were investigated by the X-ray diffraction (XRD) Rietveld refinement, transmission/field emission scanning electron microscopy (TEM/FESEM), X-ray photoelectron spectroscopy (XPS), colour measurement and UV–vis–NIR spectrophotometry. Upon increasing the calcining temperature, both Ni2+ and Mg2+ hindered the migration of Al3+ to octahedral sites. When the Ni content increased, the cation site percentage of Ni2+ in the tetrahedral and octahedral sites varied slightly while that of Al3+ and Mg2+ change substantially. The cation exchange resulted in an increase in the inversion parameters and a decrease in the lattice parameters with increasing temperature or Ni content. Furthermore, Rietveld refinement also showed a shrinkage of the tetrahedra and an expansion of the distorted octahedra in the spinel structure. Short-range information based on optical spectra suggests that variation in the splitting energy of tetrahedra and octahedra caused the change in the spectral absorption. This study may deepen the understanding of the structural-optical property relationship of NixMg1-xAl2O4 spinel, which is vital to the further colour modification of ceramics and glazes.  相似文献   

5.
The spectroscopic characteristics of Er-doped lead silicate glasses were investigated with respect to the effects of glass modifiers (Li+, Na+, K+, Mg2+, Ca2+, Sr2+, and Ba2+) with various optical basicities. Using the absorption spectra of the glasses, the Judd–Ofelt parameters of the glasses were calculated and examined, with an emphasis on the glass emission intensity ratio at 1572 nm. The spectra of the samples at low temperatures were examined, and the Stark splitting of Er3+ was investigated. The McCumber method was used to determine the emission cross sections of glasses. The SPM glass exhibited high values of full width at half maximum (51.24 nm) and the emission cross section at 1572 nm (1.908 × 10−21 cm2), with potential applications for guiding component design of 1.5-μm fiber lasers and amplifiers.  相似文献   

6.
《Desalination》1987,61(3):245-248
The uptake of Ca2+ and Mg2+ from the Arabian Gulf water of the walls of plastic and glass bottles was followed at room temperature for contact times up to 360 h. Both ions are physically adsorbed in two distinct species, which can be leached out by water and acid elution, successively. The amounts adsorbed are too little to be of practical interest. Both plastic and glass bottles can be safely used to collect and store seawater samples.  相似文献   

7.
Microsilica is commonly added to alumina–magnesia castables to counterbalance the in situ spinel expansion. This effect is attained by the generation of a low-melting temperature phase, which also affects the expansive reaction kinetics. Additionally, the MgAl2O4 formation depends on the grain size of the reactants. The use of coarse magnesia grains results in lower Mg2+ dissolution and could lead, at 1500 °C, to forsterite development (Mg2SiO4). For finer MgO, silica was detected at the edge of the spinel grains. Considering these aspects, this work evaluated the effect of microsilica content for different magnesia grain sizes (<45 or <100 μm). Due to a faster spinel formation for the fine MgO source, microsilica counterbalanced the MgAl2O4 expansion. Conversely, for the coarser MgO, silica increased the Mg2+ dissolution, speeding up the spinel formation and expansion. Therefore, microsilica presented opposite roles, pointing out that it does not always counterbalance the spinel expansion. This work also indicated the need for a systemic approach for the expanding design of alumina–magnesia refractory castables.  相似文献   

8.
The effects of various methods of mechanical strengthening of glass on the adhesion properties of poly(vinyl butyral) (PVB) film to a float glass surface were investigated. The mechanisms of the influence of the strengthening processes on the adhesion properties were analyzed. The influence of different types of pretreatment of the glass surface on the adhesion of the polymer films was also considered. It was shown that ion-exchange strengthening followed by treatment with an alkaline water solution provided the best combination of high mechanical strength of glass and good adhesion of the PVB films to the glass surface. Metal-oxide coatings on float glass increased the mechanical strength of glass but decreased the adhesion strength between the polymer and glass. The adhesion of PVB to the metal-oxide layers was determined not only by the chemical composition of the layers, but also by the method of layers formation, the type of glass surface pretreatment, and the nature of the intermediate layer between the metal-oxide layer and the glass surface.  相似文献   

9.
建滔 《玻璃》2007,34(5):12-13
在夹层玻璃生产中PVB胶片的质量直接影响制成品的质量和使用寿命.本文从胶片的来源种类来分析PVB胶片对夹层玻璃质量的影响,希望有助于中国玻璃深加工行业健康的发展.  相似文献   

10.
In this work, we report a facile method to prepare Eu2+ activated blue-emitting glass phosphor via loading Eu3+ into USY (Na28Si168Al28O384·240H2O, Si/Al ratio=6) zeolites’ cavities followed by thermal treatment in reducing atmosphere. The zeolites powders containing Eu3+ were treated at different temperatures from 800?°C to 1200?°C in flowing 5%H2 +?95%N2 ambient. The photoluminescence properties were investigated on aspects of the emission and excitation spectra, internal quantum efficiency (IQE), thermal stability and the fluorescence lifetime. The XRD patterns showed that the sample calcined at 950?°C was of pure glassy state. Under the broad 200–430?nm excitation, a strong blue emission band peaked at 451?nm with a full width of half maximum (FWHM) value of 74?nm was observed for this sample. Under the 365?nm excitation, the samples treated at different temperatures showed monotone red shift in the emission peak wavelengths with the thermal treatment temperature increasing. Transparent glass sheets were obtained from the glass phosphor powders by spark plasma sintering (SPS) at 1200?°C, 1250?°C and 1300?°C. The optical transmittance and thermal conductivity of transparent glass sheets were measured. The results indicated that this glass phosphor may be a potential candidate material for white LEDs.  相似文献   

11.
We studied flexible electrochromic devices containing phthalate derivative which showed reversible color change between water transparent and subtractive primary color by electrochemical reaction. Poly(vinyl butyral) (PVB)-based gel electrolyte was prepared to apply the flexible electrochromic device. The ionic conductivity of the gel electrolyte depended on the polymer content, and was higher than 10−4 S/cm at 25 °C at the PVB content of 33 wt%. Redox reaction of phthalate derivatives was successfully achieved in the gel electrolyte. It is revealed that PVB-based gel electrolyte works well as the material for flexible electrochromic devices showing subtractive primary colors.  相似文献   

12.
Oxidized cellulose: An application in the form of sorption filter materials   总被引:1,自引:0,他引:1  
Oxidized cellulose (oxycellulose) was very effectively used in the form of filter sheets to remove some metal ions from water and from aqueous solutions. Furthermore, oxycellulose was applied in an ion‐exchange column and in a batch process. The mechanisms of the sorption process inside oxycellulose as well as the kinetics of sorption were studied. A comparison of oxycellulose and other adsorption components such as zeolites and ion‐exchange resins was made. The affinity of oxycellulose to metal ions was determined to be in the following order: Cd2+, Zn2+ > Ni2+ ? Ca2+ > Mg2+ ? Na+. The use of oxycellulose was very effective, especially in the form of sorption filters, because this allowed us to use a simple filtration process. Moreover, the specific loading amount of the filter cake was higher for filtration than for the column process under comparable conditions. Oxycellulose in a glass column behaved similarly to an ion‐exchange resin. It showed approximately constant efficiency until the sorption capacity of the adsorbent was exhausted, and then it suddenly dropped. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

13.
《Ceramics International》2021,47(23):32666-32674
In this work, CuO-doped MgO-Al2O3-SiO2 based glasses have been synthesized successfully through conventional melt quenching method, and the effect of CuO content on the structure and properties of the glasses was investigated. The results revealed that CuO could act as a glass modifier to depolymerize the silicate network and its effect was superior to that of MgO. In addition, the main crystalline phase was α-cordierite (Mg2Al4Si5O18), indicating that copper ions did not participate in the formation of the crystalline phase, and still existed in the interstitial position. The characteristic absorption band around 750 nm owing to the 2B1g2B2g transition of Cu2+ ions appeared on the optical transmittance spectra, which confirmed the existence of Cu2+ ions in the tetragonally distorted octahedral sites. The luminescence center was caused by Cu+ ions, and the luminescence lifetime decreased with the addition of CuO. The dielectric constant and dielectric loss increased with the increase of CuO content, indicating an increase in the insulation performance. Finally, the obtained chromaticity coordinate parameters indicate that the prepared CuO-doped magnesium aluminosilicate-based glasses can be applied in optical and electrical fields.  相似文献   

14.
以电流体动力(EHD)诱导聚乙烯醇(PVA)薄膜表面微结构的形成为对象,研究了不同EHD工艺和氢氟酸刻蚀工艺对PVA薄膜微图案结构及玻璃表面微结构制备和光学性能的影响,提出了一种利用PVA微图案结构调控氢氟酸刻蚀玻璃表面制备光学微结构的新方法。结果表明,改变EHD诱导电压和PVA薄膜初始厚度可以得到区别化的PVA薄膜微图案,而改变氢氟酸浓度和刻蚀时间可以将微图案刻蚀到玻璃表面并在玻璃表面形成一系列不同的微结构;经处理后的玻璃表面较未使用PVA薄膜的玻璃具有更高的雾度和透射率。  相似文献   

15.
The effects of poly(vinyl butyral) (PVB) and acid‐functionalized multiwalled carbon nanotube modification on the thermal and mechanical properties of novolac epoxy nanocomposites were investigated. The nanocomposite containing 1.5 wt % PVB and 0.1 wt % functionalized carbon nanotubes showed an increment of about 15°C in the peak degradation temperature compared to the neat novolac epoxy. The glass‐transition temperature of the novolac epoxy decreased with increasing PVB content but increased with an increase in the functionalized carbon nanotube concentration. The nanocomposites showed a lower tensile strength compared to the neat novolac epoxy; however, the elongation at break improved gradually with increasing PVB content. Maximum elongation and impact strength values of 7.4% and 17.0 kJ/m2 were achieved in the nanocomposite containing 1.5 wt % PVB and 0.25 wt % functionalized carbon nanotubes. The fractured surface morphology was examined with field emission scanning electron microscopy, and correlated with the mechanical properties. The functionalized carbon nanotubes showed preferential accumulation in the PVB phase beyond 0.25 wt % loading. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43333.  相似文献   

16.
Recovery of alginate extracted from aerobic granular sludge (AGS) has given rise to a novel research direction. However, these extracted alginate solutions have a water content of nearly 100%. Alternately, ultrafiltration (UF) is generally used for concentration of polymers. Furthermore, the introduction of multivalent metal ions into alginate may provide a promising method for the development of novel nanomaterials. In this study, membrane fouling mitigation by multivalent metal ions, both individually and in combination, and properties of recycled materials were investigated for UF recovery of sodium alginate (SA). The filtration resistance showed a significantly negative correlation with the concentration of metal ions, arranged in the order of Mg2+ < Ca2+ < Fe3+ < Al3+ (filtration resistance mitigation), and the moisture content of recycled filter cake showed a marked decrease. For Ca2+, Mg2+, Fe3+, and Ca2++ Fe3+, the filtration resistances were almost the same when the total charge concentration was less than 5 mmol⋅L–1. However, when the total charge concentration was greater than 5 mmol⋅L–1, membrane fouling mitigation increased significantly in the presence of Ca2+ or Fe3+ and remained constant for Mg2+ with the increase of total charge concentration. The filtration resistance mitigation was arranged in the order of Fe3+ > Fe3+ + Ca2+ > Ca2+ > Mg2+. Three mechanisms were proposed in the presence of Fe3+, such as the decrease of SA concentration, change in pH, and production of hydroxide iron colloids from hydrolysis. The properties of recycled materials (filter cake) were investigated via optical microscope observation, dynamic light scattering, Fourier transform infrared, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy. The results provide further insight into UF recoveries of alginate extracted from AGS.  相似文献   

17.
The morphology of poly(ε‐caprolactone) (PCL)/poly(vinyl butyral) (PVB)/clay nanocomposites was studied as a function of a small amount of amorphous PVB by polarized optical microscopy. The band spacings of PCL spherulites in PCL/PVB/clay nanocomposites decreased with increasing PVB content, and this indicated that increasing the PVB content shortened the period of lamellar twisting. The electrical properties of PCL/PVB/clay nanocomposites containing carbon black (CB) were also measured as a function of the PVB content. For samples with the same CB content, the intensity of the positive temperature coefficient (defined as the ratio of the peak resistivity to the resistivity at room temperature) of the nanocomposites increased as the PVB content increased. The change in the positive temperature coefficient was related to the morphological differences (i.e., the period of lamellar twisting) in the nanocomposites. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1022–1031, 2003  相似文献   

18.
In this study, tannin extracted from Terminalia chebula (Aralu) was used to produce tannin–phenol–formaldehyde resins. They were produced to obtain resins with different tannin to phenol ratio in an attempt to optimize the ion exchange capacities of resins produced. The resins made were sulfonated to improve their properties further. Bivalent cations, such as Zn2+, Pb2+, Ca2+, Mg2+, and Cu2+, were used to estimate the adsorption properties of both unsulfonated and sulfonated resins. The glass transitions of representative resins were estimated using differential scanning calorimeter thermograms. Fourier transform infrared spectroscopic analysis was used to gauge changes on resins by sulfonation and adsorption of cations. The glass transition values of unsulfonated, sulfonated, and metal‐adsorbed sulfonated resins showed a similar increasing trend with the increase of phenol content in the resin. The glass transition temperature values reach a plateau beyond the tannin/phenol ratio of 1 : 0.5, indicating the formation of large molar masses facilitating entanglements beyond that ratio. The phenol ratio of 1 : 0.5 has shown the highest adsorption capacity for all the metal ions used. The highest adsorption capacity was shown for sulfonated tannin–phenol–formaldehyde resin with the tannin/phenol ratio of 1 : 0.5 for Pb2+, which is 0.610 meq/g. The adsorption equilibrium data obtained using the column technique were found fitting Freundlich isotherm. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

19.
Plasticized polyvinyl butyral (PVB)‐silica nanocomposite films were formed by mixing PVB ethanol solution and silica sol, which was prepared from tetraethyl orthosilicate. The nanocomposite films were colorless and transparent even though the content of silica was 70 wt%. The glass transition temperature of PVB in the silica 2.5 wt% nanocomposites was higher by about 10°C than that of plasticized PVB. The PVB‐silica nanocomposite films were applied as an interlayer for laminated glass. The laminated glass made with the nanocomposite films containing less than 10 wt% silica showed good penetration resistance, not only at room temperature but also at 70°C. J. VINYL ADDIT. TECHNOL., 25:E59–E63, 2019. © 2018 Society of Plastics Engineers  相似文献   

20.
The effect of polyvinyl butyral (PVB) resins on the gelation behavior of the BaTiO3-based dielectric particles and borosilicate glass particulate suspensions was investigated in a system where organic solvents, dispersant, binder and gelation modifier were used as processing additives in a low temperature cofired ceramic fabrication processes. The strong flocculation, gels of the suspension without a modifier was attributed to the reaction and strong linkage between the boron in the borosilicate glass and the functional hydroxyl group of PVB resins, which was confirmed by Fourier transform infrared spectroscopy and scanning electron microscopy. When the butyral content of PVB employed in each slurry formulation diminish by approximately 8%, it caused the concentrated suspension to gel. The butyral content of PVB had a much greater impact on gelation than did the molecular weight of PVB. As the molecular weight of PVB was increased, the apparent viscosities of the slurries increased due to the broader chain length of higher molecular weight of PVB. According to the relative viscosity measurement results, both suspensions with high and low PVB molecules had similar viscosity values and it might be regarded as the more viscous feature of PVB polymer solution.  相似文献   

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