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1.
This discussion of the past regulatory trends and current developments for the vinyl industry will provide an overview of the regulatory world that producers and fabricators of poly(vinyl-chloride) face today, with some projections of what the future may hold. By considering past regulatory trends and current developments, projecting future developments can be more than mere speculation. Because environmental issues are very complex and challenging, the overview begins and concentrates there. The focus will also discuss OSHA regulations, pending actions of EPA, California's Proposition 65, and Consumer Product Safety Commission's regulation of phthalates. The overview will conclude with an analysis of projected specific regulatory actions including: reducing VCC emissions, additional restrictions on land disposal, demands that vinyl products demonstrate that they fit the general solution to the solid waste crisis, and coping with state and local regulations that pose conflicting or unreasonable requirements.  相似文献   

2.
The Geon Company and the vinyl industry have been very active in recycling for a number of years. A significant portion of that effort has been focused on the vinyl packaging, and the industry has been instrumental in getting automatic bottle sortation commercialized. This paper will focus more on vinyl durables recycling in wire and cable, computer and business equipment, and automotive. In addition it will address a number of environmental attacks currently leveled at vinyl.  相似文献   

3.
ZnO/MgO, ZnO/CaO, and ZnO/CaO/MgO can form solid solutions. The solid solution for we as flame retardant (SSFR) was obtained by annealing at 1023 K for 4.5 h in a muffle furnace. Flexible poly (vinyl chloride) (PVC) filled with SSFR and Sb2O3 was investigated by differential thermal analysis thermogravimetry. Limiting oxygen index (LOI), mechanical properties, and electrical properties were studied. The surface of the char formed after combusting of the PVC compounds was observed through scanning electron microscopy and the effect of the surface area to the LOI was also studied. The data suggested that a small amount of SSFR and Sb2O3 have good synergy and can greatly increase the LOI and the char yield, and that the thermal degradation temperature and the activation energy decreased. It can be concluded that the mechanism of SSFR is a condensed‐phase mechanism. Moreover, one can conclude that the surface area can enhance the LOI. All the results showed that SSFR is effective and safe as a flame retardant in flexible PVC. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3137–3142, 2003  相似文献   

4.
In this study, the effect of the high‐energy mechanical milling of a mixture of poly(vinyl chloride) (PVC) with zinc borate (ZB) or ZB–aluminum trihydrate (ATH), a mixture of ZB and ATH, on the flame‐retardant and mechanical properties of ZB and ZB–ATH filled PVC was examined. The high‐energy mechanical milling of PVC/ZB and the PVC/ZB–ATH mixture produced chemical bonding between PVC and ZB or ZB–ATH, increasing the interfacial interaction of PVC/ZB and PVC/ZB–ATH blends, which resulted in a great increase in the limiting oxygen index, the impact and yield strengths, and the elongation at break of PVC/ZB and PVC/ZB–ATH blends. The results from ultraviolet spectroscopy and gas chromatography–mass spectroscopy show that mechanochemical modification of ZB and ZB–ATH much more effectively suppressed the release of aromatic compounds in PVC/ZB and PVC/ZB–ATH blends during burning. Mechanochemical modification provided an excellent route for the improvement of the flame‐retardant and mechanical properties of flame‐retardant‐additive‐filled PVC. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 753–762, 2003  相似文献   

5.
There is a growing interest in the use of polyolefins and their copolymer blends in cable industries. The present investigation deals with the development of thin‐walled halogen‐free cable insulation and thin‐walled halogen‐free fire‐resistant low‐smoke cable sheathing compounds based on polyolefin elastomer (Engage®) and ethylene vinyl acetate (EVA) blends. Blends of Engage (an ethylene octene copolymer) and EVA, varying in proportions, are prepared on a two‐roll mixing mill at an elevated temperature. Physicomechanical, electrical, and the most important flame‐retardant properties of the dicumyl peroxide/triallyl cyanurate cured blends have been basically studied. Properly compounded Engage‐EVA blends are found to be excellent materials in cable industry for insulation as well as for sheathing compounds. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

6.
Polysilphenylenesiloxanes containing various amounts of vinyl substituents (ranging from partial (25 %) to complete (100 %)) on the silicon atoms were synthesized. 29Si NMR spectroscopy revealed that they had a well defined structure, as designed. Unlike the known crystalline poly(tetramethyl‐p‐silphenylenesiloxane), all polymers containing vinyl side groups were amorphous and showed low Tgs, ranging from ?52 to ?32 °C (from differential scanning calorimetry (DSC)). Dynamic and isothermal thermogravimetric (TG) analyses indicated that they all possessed a greatly improved thermal stability up to 500 °C, and have ultra‐high residual yields at 1000 °C under both inert and oxidative conditions. Polysilphenylenesiloxanes containing a high percentage of vulcanizable vinyl substituents should be excellent candidates for high‐temperature polymers and have potential applications such as heat‐resistant or flame‐retardant materials. Copyright © 2004 Society of Chemical Industry  相似文献   

7.
The flame‐retardant and smoke‐suppressant properties of inorganic tin compounds such as zinc hydroxystannate (ZHS) and zinc stannate (ZS) were studied in comparison with those of alumina trihydrate and magnesium hydroxide through the limiting oxygen index test and a smoke density test. The thermal degradation in air of flexible poly(vinyl chloride) (PVC) treated with the above compounds was studied by thermal analysis from ambient temperature to 800°C. The activation energy was calculated by using the Vyazovkin model‐free kinetic method and the Kissinger method. The results showed that tin compounds such as ZHS and ZS could be used as highly effective flame retardants for flexible PVC; these flame retardants enhanced the stability and the activation energy of the oxidation of the char. J. VINYL ADDIT. TECHNOL, 2008. © 2008 Society of Plastics Engineers  相似文献   

8.
Radiation-initiated polymerization of vinyl phosphonate oligomer (molecular weight 500–1000) and N-methylolacrylamide from aqueous solutions was investigated with cotton printcloth, flanelette, and sateen fabrics and with cotton (50%)–polyester (50%) flannelette fabrics. Determinations were made of the effects of radiation dosage, mole ratio of vinyl phosphonate in the oligomer to N-methylolacrylamide in aqueous solution, concentration of reactants, wet pickup of solutions on fabrics, and irradiation of both dry and wet fabrics on efficiency of conversion of oligomer and monomer in solution to polymer add-on. The effects of vinyl phosphonate oligomer and N-methylolacrylamide radiation-initiated polymerization on some of the textile properties of cotton printcloth and on flame resistances of cotton and cotton–polyester fabrics were evaluated. The breaking strength of modified cotton printcloth was about the same as that of unmodified fabric; however, the tearing strength and flex abrasion resistance of modified fabric were reduced. The textile hand of the modified printcloth fabrics that had flame resistance indicated: interaction between cellulose and vinyl phosphonate oligomer–poly(N-methylolacrylamide) and uniform deposition in the fibrous cross section (transmission electron microscopy); surface areas of heavy deposits of oligomer–polymer (scanning electron microscopy); and phosphorus located throughout the fibrous cross section (energy dispersive x-ray analysis). Polymerization of vinyl phosphonate oligomer and N-methylolacrylamide was radiation initiated with cotton–polyester fabric; however, this modified fabric did not have flame-resistant properties.  相似文献   

9.
Ethylene‐vinyl acetate (EVA) nanocomposites with enhanced flame retardance were prepared by the sol–gel process in the melt. Two EVAs with different vinyl acetate (VA) contents and aluminium isopropoxide were used as organic and inorganic phases. The nanocomposites were prepared in a batch mixer under constant processing conditions and were analysed by several characterization techniques. Aluminium isopropoxide presented low activation energy, which allows the synthesis of the nanoparticles without a post step treatment. The reaction mechanism is proposed. Nanocomposites with smaller and well dispersed metal nanoparticles were produced with an EVA with higher VA content. EVA nanocomposites achieve the requirements for 94 V‐0 classification. © 2013 Society of Chemical Industry  相似文献   

10.
Metal hydroxystannates were studied as flame retardants and smoke suppressants for semirigid poly(vinyl chloride) (PVC). The flame‐retardant and smoke‐suppression mechanisms were investigated by using limiting oxygen index (LOI), smoke density rating (SDR), the solid yield test (SY), scanning electron microscopy (SEM), thermogravimetry, differential thermogravimetry, and differential thermal analysis. Results showed that semirigid PVC treated with the flame retardants had a higher LOI, and solid yield, but a lower SDR and maximum smoke density, thereby indicating that the flame‐retardance and smoke‐suppression properties of the treated PVC were improved and that the hydroxystannate compounds could be used as highly effective flame retardants. The tin compounds may exert their action in both the condensed and vapor phases, but mainly in the condensed phase as Lewis acids. J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers.  相似文献   

11.
A crying need of the day in India is to supply safe drinking water to its villages, towns and cities. Though the urban needs are partially met by organized water supply schemes, acute water shortages are felt at various times in this sector also with the expanding industrialization of the country. In many areas of arid and semi-arid regions, only brackish waters are available which are unfit for human consumption.Research and development effort at CSMCRI on the two membrane processes, reverse osmosis and electrodialysis, during the past decade has been reviewed. Some of the current activities in the rural sector and the future potential for these two processes in tackling the pressing needs of potable water to the rural masses in India are outlined. In the industrial sector, these two processes have immense potentialities in pollution abatement and water reuse.  相似文献   

12.
Additives that act as flame retardants can contribute significantly to smoke generation because they decrease the efficiency of the fuel source and, as a result, create a sooty combustion. Work on a new phosphate ester material has shown interesting results and synergies that complement both flame retardancy and low smoke generation in flexible vinyl compositions. This new proprietary aryl phosphate was examined in both neat and blended systems and compared to other typical phosphate ester fire‐retardant (FR) compounds for vinyl. Additionally, the flammability and smoke effects were measured with and without other common vinyl FR additives (zinc borate and ammonium octamolybdate). J. Vinyl Addit. Technol. 10:187–192, 2004. © 2004 Society of Plastics Engineers.  相似文献   

13.
摘要: 综述了近几年有关氢氧化铝及其复合体系对聚氯乙烯(PVC)阻燃性能和抑烟性能的研究进展,对氢氧化铝改性PVC阻燃性能和抑烟性能的影响因素、氢氧化铝的协同阻燃剂和抑烟剂进行了分类,并展望了改性剂未来在防辐射、抑菌等方面的发展方向。  相似文献   

14.
石化产业节能降碳,既是行业自身转型的现实需要,也是服务全社会碳达峰、碳中和目标实现的重要一环.石化产业能耗总量大、化石能源消耗占比高且替代难度大、碳排放总量较高,2019年我国石化产业能耗总量约1.7亿吨标煤,碳排放总量约4.7亿吨.未来我国油品消费将较快达峰,但化工产品的消费量仍有一定时期的较大增长需求,在统筹经济社...  相似文献   

15.
Syndiotacticity‐rich poly(vinyl alcohols) (s‐PVAs) with various syndiotactic dyad (S‐dyad) contents were prepared by the copolymerization of vinyl pivalate and vinyl acetate with various monomer feed ratios, which was followed by the saponification of copoly(vinyl pivalate/vinyl acetate) to investigate the effect of the stereosequences of s‐PVA on the rheological properties of s‐PVA/water solutions. Through a series of experiments, we identified that the syndiotacticity had a profound influence on the rheological properties of s‐PVA/water solutions. Over a frequency range of 10?1 to 102 rad/s, s‐PVAs with higher S‐dyad contents showed larger values of complex viscosity and storage modulus and more shear thinning at similar molecular weights and degrees of saponification of the polymer, suggesting that poly(vinyl alcohol) molecules were stiffer and more readily oriented as syndiotacticity increased. All the yield stresses of s‐PVA represented positive values, and s‐PVAs with higher syndiotacticity showed higher yield stresses. This suggests that as syndiotacticity increased, more pseudostructures were present in s‐PVA/water solutions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1858–1863, 2003  相似文献   

16.
综述了氯乙烯合成工艺的最新研究进展,讨论了不同工艺以及催化剂的优缺点。将无汞工艺与目前国内比较成熟的含汞工艺进行了比较,指出了无汞工艺法是国内未来氯乙烯合成工艺的发展趋势。  相似文献   

17.
Al(OH)3 as flame retardant and smoke suppressant for flexible poly(vinyl chloride) was evaluated alone and with ZnO, using thermal analytical techniques, limiting oxygen index and smoke density rating tests. The thermal behavior and flammability of the samples treated with Al(OH)3 and ZnO were studied by differential thermal analysis and thermogravimetric analysis. The activation energy was calculated by using the Vyazovkin model‐free kinetic and Kissinger methods. The results showed that the flame‐retardant and smoke‐suppressant properties of the samples treated with Al(OH)3 and ZnO were related to the content of ZnO and the thermal effect during the process of thermal degradation of the samples. Copyright © 2005 Society of Chemical Industry  相似文献   

18.
Ethylene vinyl acetate (EVA) copolymer with varying vinyl acetate (VAc) content, viz. 18%, 28% and 40% has been hydrolyzed using alcoholic NaOH solution. Fourier Transform Infrared Spectroscopy (FTIR) analyses of hydrolyzed polymer showed the presence of both OH group and acetate group indicating that the EVA has been partially hydrolyzed. Differential Scanning Calorimeter (DSC) and Thermo Gravimetric Analyzer (TGA) of EVA and hydrolyzed EVA showed large difference in melting and decomposition temperature, respectively. Hydrolyzed EVA showed higher tensile strength and elongation at break compared to corresponding EVA. Blends of different grades of EVA and ethylene vinyl alcohol (EVAl) with low density polyethylene (LDPE) were applied on grit blasted mild steel surface by flame spray technique. FTIR analysis of blends before and after coating showed no degradation during flame spray. Measurement of adhesion strength of these coating showed that adhesion strength increased on hydrolysis of EVA.  相似文献   

19.
氧化锌和氢氧化物对软聚氯乙烯阻燃性能的影响   总被引:4,自引:0,他引:4       下载免费PDF全文
引言 软质PVC制品中由于大量增塑剂的加入,大大提高了其可燃性,燃烧时还会产生大量有毒烟雾,因此对PVC制品的阻燃抑烟问题亟待解决.无机氢氧化物优点众多,在阻燃高分子材料中应用广泛,但阻燃效率低,常与其他阻燃剂复配使用.硼酸锌、锡酸锌、磷酸锌、氧化锌等可直接或与其他阻燃剂复合应用于PVC的阻燃消烟[1-3].  相似文献   

20.
A novel oligomeric phosphorous–nitrogen‐containing intumescent flame retardant poly (2,6‐diaminopyridine spirocyclic pentaerythritol bisphosphonate) (PDSPB) is synthesized, and subsequently multiwalled carbon nanotube (MWNT)‐grafted oligomeric intumescent flame retardant, MWNT‐g‐PDSPB, is fabricated via chemical grafting reaction and characterized. The grafting reaction was characterized by FTIR, NMR, and XPS. After high‐density PDSPB (88 wt%) were attached to the MWNTs, core‐shell nanostructures with MWNTs as the hard core and PDSPB as the soft shell were formed. The resultant MWNT‐g‐PDSPB was soluble and stable in polar solvents, such as DMF and DMSO. MWNT‐g‐PDSPB has excellent thermal stability and charring ability. The TEM results showed that the functionalized MWNTs could achieve better dispersion in poly(ethylene vinyl acetate) (EVA) matrix. The residue char of MWNT‐g‐PDSPB is as high as 70 wt%, and the grafting of intumescent flame retardant of PDSPB can improve both the dispersion of MWNTs in polymer matrix and flame retardancy of the nanocomposites. POLYM. COMPOS., 2013. © 2012 Society of Plastics Engineers  相似文献   

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