Tung函数法计算聚氯乙烯的分子量及其分布

本文详细讨论了采用童展和函数法和董履和函数近似法对聚氯乙烯的分级数据的处理过程，获得了聚氯乙烯的Ｍｎ。Ｍｗ、和Ｍｎ及多分散指数，并作出了聚氯乙烯的重量微分分子量分布曲线图和重量积分分子量分布曲线图．

Study on Immobilized Lipase Catalyzed Transesterification Reaction of Tung Oil

The transesterification reaction conditions of tung oil with methanol have been studied in this article, with immobilized lipase NOVO435 as catalyst. The response surface methodology was used to optimize the transesterification reaction of tung oil in a nonsolvent system. The optimal conditions were rotation rate 200 r/min, molar ratio of methanol to oil 2.2： l, reaction temperature 43℃, and the catalyst amount 14% （based on the weight of oil）. After reacting for 18 h, 67.5% of the oil was converted to its corresponding methyl esters （the theoretical ester conversion was 73.3%）. The lipase was washed by organic solvents after each reaction and was reused again. The esters conversion of tung oil was decreased by 6% after the lipase was reused for 120 h. The theoretical amount of methanol was added in two steps, 85% ester conversion was obtained after 36 h of reaction （theoretical ester conversion was 100%）. The molar ratio of methanol to oil, the catalyst amount, the reaction temperature, and reaction time were all highly significant factors, and there was a relative significant interaction between every two factors.

Preparation and characterization of tung oil-based flame retardant polyols

Three kinds of tung oil-based structural flame retardants polyols(TOFPs) were prepared by new methods in this paper. First, tung oil was used to produce monoglyceride and diglyceride by transesterification with glycerol by sodium methoxide. The products after transesterification were epoxidized by peracetic acid which was in-situ generated from acetic acid and hydrogen peroxide in the presence of sulfuric acid catalyst. And then, TOFPs were prepared from epoxidized alcoholysis tung oil(EGTO) with 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide(DOPO), diethyl phosphate(DEP) and diethanolamine(DEA) by ring-opening reactions, respectively. GPC was used to evaluate the conversion rate, at optimum reaction conditions, selectivity for monoglyceride in transesterification. The influence of different parameters such as temperature, mole ratio or mass ratio on the conversion rate of transesterification and epoxidation were investigated. The molecular structures of TOFPs were characterized by FTIR and ~1HNMR. Finally, tung oil-based polyurethane foams(TOPUFs) were prepared by a one-shot process using TOFPs with polyisocyanate. The LOI values of TOPUFs whose content of DOPO-EGTO,DEP-EGTO and DEA-EGTO were 100 wt% can reach to 26.2%, 25.1%, and 24.4%, respectively.

Photocatalytic degradation of MO by complex nanometer particles WO_3/TiO_2

Complex nanometer particles WO3/TiO2 were prepared using a sol-gel process and characterized using XRD spectra. The photocatalytic activity of TiO2 can be increased by doping W^6＋ with TiO2 because the doped W^6＋ that entered into the crystal lattices of TiO2 led to the formation of defects in the crystal lattices of TiO2 and thereby improved the photocatalytic activity of TiO2.When WO3 doped in TiO2 exceeded 3%, the excess W^6＋ did not enter into the crystal lattices of TiO2 but were uniformly dispersed in TiO2 or they covered the surface of TiO2, which reduced the effective illumination area of TiO2 and thereby lowered the photocatalytic activity of TiOE.The relationship among the composition of the catalyst, the amount of photocatalyst, the illumination time, and the decolorizing rate of methyl orange （MO） were discussed. The results show that the decolorizing rate of MO can reach 82.3% using WO3/TiO2 as the photocatalyst, with the composition of WO3/TiO2 -3：97, the mass of catalyst = 0.400 g, the initial concentration of MO = 20 mg/L, pH = 6.5, and the illumina- tion time = 7 h.

Synthesis and Properties of Novel Non-Ionic Polyurethane Dispersion Based on Hydroxylated Tung Oil and Alicyclic Isocyanates

Hydroxylated Tung oil (HTO) based nonionic polyurethane dispersion (HTO-NPUD) were synthesized using dicyclohexyl methane diisocyanate (HMDI) and HTO as main hydrophobic materials whereas polyethylene glycol-800 (PEG-800) as hydrophilic chain extender. To effectively study the effects of HTO on properties of NPUD, polypropylene glycol-400(PPG-400) based NPUD was prepared by HMDI reacting with PPG-400 and PEG-800. The structures of those novel nonionic polyurethane dispersions were characterized by FTIR and 1H NMR. Moreover, particle size and size distribution, cloud point and surface tension had been investigated. Results showed that, by comparing with PPG based NPUD (PPG-NPUD), the introduction of HTO into NPUD result in larger particle size and more uniformed particle size distribution, higher cloud point and lower surface tension.

Study on Toughening Phenolic Foams in Phosphorus-Containing Tung Oil-Based Derivatives

Phenolic foams(PFs)as thermal insulation material with outstanding flame retardancy are required to match society’s ever-expanding safety expectations;however,a trade-off exists between flame retardancy and toughness.Here,for the first time,we synthesized a novel reactive phosphorus-containing tung-oil-based derivative and used it to toughen PF,resulting in PFs with a combination of excellent mechanical properties and flame retardancy.Compared with pure PF,the modified PFs exhibit enhanced mechanical properties,with specific compressive and flexural strengths as high as 5.67 MPa and 12.46 MPa,which represent increases of 90.67%and 178.7%over those of pure PF,respectively.Meanwhile,the limiting oxygen index(LOI)values of the modified PFs are improved as much as 40.83%.Scanning electron microscopy micrographs show that the microstructure of the modified PFs is better than that of pure PF,with a more uniform cell morphology,a narrower pore size distribution range,and a smaller average pore size,all of which are beneficial to the foam’s mechanical properties.This study provides a scientific paradigm for the development of advanced PFs based on renewable biological resources.

Preparation and Characterization of Tung Oil Toughened Modified Phenolic Foams with Enhanced Mechanical Properties and Smoke Suppression

In this study,we prepared a series of tung oil phenolic foams(TPF)by a one-pot method.The FT-IR and 1H NMR spectra confirm the successful Friedel-Crafts grafting of phenol to the long-chain alkyl group in tung oil.Modified TPFs exhibit enhanced mechanical properties,including compressive and flexural strengths of up to 0.278±0.036 MPa and 0.450±0.017 MPa,respectively,which represent increases of 68.75%and 86.72%over those of pure phenolic foam(PF).SEM spectra reveal the TPF microstructure to have uniform hexagonal cell morphology,narrower cell size distribution,and smaller mean cell size,suggesting enhanced mechanical properties.The TPF total smoke release decreased by 74.23%,indicating that the long alkyl chain significantly improves smoke suppression of the combusting foam.However,due to the flammability of the alkyl chains,the TPF limiting oxygen index decreases with increasing tung oil content.Moreover,TPF exhibits reduced thermal stability and high-temperature charring rate,elevated peak and mean heat release rates,and higher total heat release compared with pure PF.Therefore,future research will focus on the use of tung oil modified flame retardant to provide more robust phenolic foams.

A Preliminary Study of Three Finishing Materials for Traditional Chinese Furniture

The traditional Chinese furniture evolved as an important part of the Chinese culture and civilization. Alongside design, structure, ornaments, the original finishes applied define the particularities and value of traditional Chinese furniture. This is because wood finishing not only enhances wood natural beauty by colour, gloss and highlighting of wooden texture, but also can be a means of exquisite decoration (e.g. engraved, gilded or painted lacquer works). Chinese lacquer, Tung oil and Chinese wax represent some of the most important finishing materials employed and were, therefore, selected for this study. The paper presents a brief macroscopic, microscopic and FTIR characterization of these materials. These results will be used as starting data in a further study on the ageing properties of these traditional finishing materials, useful for scientific conservation purposes.

Preparation and Properties of Tung Oil-Based Polyurethane

Tung oil-based polyols were synthesized by the esterification and transesterification between Tung oilbased anhydride and butanediol. The hydroxyl values of the polyols prepared were tested and discussed. Polyurethane was prepared by using Tung oil-based polyols and/or poly(propylene glycol) as polyols and by using isophorone diisocyanate as isocyanate. The effect of the ratio of Tung oil-based polyols to poly(propylene glycol) on the properties of polyurethane prepared was investigated by the water resistance, alcohol resistance and hardness tests. The results show that Tung oil-based polyols are effective to improve the hardness, water resistance and alcohol resistance of polyurethane.

Research Progress of Tung Oil/UV Photocomposite Curing Material

Tung oil(TO)/ultraviolet(UV)photo-composite curing material possesses the characteristics of low curing temperature,low material shrinkage and low environmental pollution.Accordingly,this material must be developed and utilized with the conjugated double bonds contained in the long chain of the main structure(α-tung acid)molecules in the refined TO.The aforementioned material can be chemically modified using a variety of chemical methods to develop a new TO-based UV photocurable material due to its unique chemical properties.This work reviews the research progress of TO/UV photo-composite curing materials in recent years.Firstly,the chemical structure and application of TO and UV Photocatalysis Technology were briefly introduced.Secondly,the research status of novel TO/UV photo-composite curing materials developed by the Diels-Alder reaction was discussed.The method and curing effect of the UVcuring system constructed by other chemically modified TO were also discussed.Thereafter,the application of TO in industrial production is introduced from four directions:the application of TO in biodiesel,the application in synthetic resin,the application in self-healing coating and microcapsules and other applications.Finally,the research and application prospects of TO/UV photo-composite curing materials were presented.

Technology and kinetics of free fatty acids esterification in tung oil

We studied the esterification of free fatty acids （FFA） in tung oil with methanol by using activated carbon treated with sulfuric acid as a catalyst, and investigated the effect of different temperatures, methanol/oil mole ratio and catalyst amount on the conversion of FFA. Results show that the optimal reaction condition is when the reaction time is 2 h, the mass fraction of the catalyst to total material is 5%, the molar ratio of menthol to FFA is 15 ： 1, and the reaction temperature is 368.15 K. We also investigated the kinetics of estefification at various temperatures. Results indicate that the rate-control step could be attributed to the surface reaction, and within the range of the experimental conditions, the as-calculated kinetics formula can depict the esterification processes well.

Insight into Hydrolytic Stability and Tribological Properties of B-N Coordination Tung Oil-Based Lubricant Additive in Water

A tung oil-based boron-nitrogen coordination polymer(TWE-BN)was specially designed and synthesized as a highly efficient water-based lubricant additive,which has been beneficial to both energy conservation and conducive to environmental protection.Its hydrolysis stability and tribological properties in water were investigated.To better research the lubricating properties,and thus to understand the interaction between the surface and the lubricating additives.Herein,both experimental and theoretical computations based on density functional theory(DFT)were performed.The addition of TWE-BN reduces the water friction coefficient and wear scar diameter,and the maximum non-seizure load increased from 93 to 726 N.Moreover,the anti-corrosion ability on copper was classified as 1b level.The stainless-steel surface was analyzed using scanning electron microscopy(SEM)and X-ray photoelectron spectroscopy(XPS).In hydrolytic stability testing,TWE-BN was better than nitrogen-free tung oil-based lubricant additive(TWE-B)and remained non-hydrolyzed for at least 15 days,implying the feasibility of tung oil-based boron-nitrogen coordination as highly effective and hydrolytic stability lubricant additives.

Multifunctional Lubricant Additive Improves Lubrication and Antioxidation Properties of Tung Oil

It is of considerable significance to develop efficient and environmentally friendly machinery lubricant additives because of the increasing depletion of petrochemical resources and severe environmental problems.Herein,we proposed a facile strategy to synthesize a multifunctional vegetable oil-based lubricant via the lignin derivative vanillin coupled to amine and diethyl phosphite to produce a lubricating additive with both extreme pressure and antioxidant properties.Compared with pure tung oil,the lubricating and antioxidant performance of tung oil is significantly improved after adding additives.Adding the 1.0 wt%additive to the tung oil reduced the friction wear coefficient and the volume,and the oxidation induction time was much longer than pure tung oil.

Season, Environment Stress and Refrigerated Storage Affect Genomic DNA Isolation of Tung Tree

Many metabolites in leaf tissue disturbed plant genomic DNA isolation and always varied when leaves was harvested from different environments. Objective of this study was to investigate whether season, environment stress and refrigerated storage affect genomic DNA isolation of tung tree leaves. Five types of young leaves and two DNA isolation protocols, the recycling CTAB protocol I and II, were adopted to carry out the experiment. Our results showed that both leaf type and protocol affected DNA isolation of tung tree. Using the recycling CTAB protocol II, though little DNA were obtained from three types of young leaves, the other two have satisfying results. Whereas the recycling CTAB protocol I could produce high yield genomic DNA from all the five types of young leaves. All the detectable DNA samples in agarose gel electrophoresis were good templates for PCR reaction. Season, environment stress and refrigerated storage had a big effect on genomic DNA isolation of tung tree. The recycling CTAB protocol I was proved to be an effective and universal protocol for DNA isolation of tung tree. Five types of young leaves could all act as the tissue for isolation of genomic DNA, but the summer healthy young leaves without long-time refrigerated storage are the best. The optimal leaf tissue will benefit DNA isolation of plant species.

Effects of Xenia on Fruit and Seed in <i>Vernicia fordii</i>

Tung tree, Vernicia fordii, is a plant species producing industrial oil (tung oil). Although the cultivation of the tung tree produces great economic value, some important genetic and physiological traits in V. fordii have not been fully recognized. As one of them, the effect of pollen on the maternal plant (xenia) is unknown in V. fordii, which is an important part of the efficient cultivation system of many crops. This study performed hybridization with three important tung cultivars (Dami, Xiaomi and Putao) to evaluate the influence of pollen source on fruit and seed development. The results revealed that xenia is present in V. fordii, which influences fruit setting, fruit size, seed weight and oil content. Among the cultivars investigated, the hybridization combination with Putao as a female parent and Dami as male parent showed significant improvement of seed yield and oil content than self-pollination, which could be considered to apply in practice.

Evaluation of Tung Oil(Vernicia fordii(Hemsl.))for Controlling Termites

In worldwide,the use of chemical pesticides to protect wood has been greatly restricted.In recent years,a large number of researchers devoted to the search for natural,safe and non-polluting bioactive chemical compounds from plants as an alternative to synthetic organic chemical preservative.In Chinese folk,tung oil can be used as paint for wooden furniture to protect them from pests.This study aimed to evaluate the chemical compositions of raw and heated tung oil and their activity against termite.In choice bioassays,weight loss of wood treated with 5%raw or heated tung oil after 4 weeks was significantly less than that of the control group.In no-choice bioassays,there was a significant difference in termite survival and wood weight loss on raw and heated tung oil-treated wood.When tung oil-treatment concentrations increased to 5%,wood weight loss was less than 10%.There was no significant difference in termite survival and wood weight loss between raw and heated tung oil-treated wood.Survival of termites in both tung oil wood treatments was significantly lower than that in the starvation control after 4 weeks.Raw and heated tung oil significantly improved the resistance of pine wood to termites,and have the potential for the development of natural wood preservatives.

Leading Nonferrous Enterprises Kicked Off Acquisitions Frequently

The huge adjustment in the stock market since June inadvertently opened another door:In the sluggish nonferrous industry,a number of"long stagnant"asset acquisition projects have kicked off.Recently,Xiamen Tungsten disclosed details of its acquisition of Jiangxi Tungsten assets,