Effect of penta- and tetramethyl HALS on the radiation resistance of polypropylene

2,2,6,6-Tetramethyl-4-piperidinyl methacrylate (TMPM), a new pentamethyl HALS 1,2,2,6,6-pentamethyl-4-piperidinyl methacrylate (PMPM), their homopolymers (PTMPM and PPMPM), and their copolymers, [i.e., TMPM or PMPM copolymerized with monomers methyl methacrylate (MMA), methacrylic acid (MAA), acrylic acid (AA), and styrene (St) separately] were synthesized. PMPM shows an extremely excellent stabilizing effectiveness on improving the radiation resistance of polypropylene (PP) in comparison with other low molecular weight (LMW) HALS or polymeric HALS. Polymeric HALS shows a much higher thermal stability and better extraction resistance than that of LMW HALS. It is found that the Eb values of the PP-added pentamethyl HALS series are higher than those of PP with the corresponding tetramethyl HALS series at a given irradiation dose. A conclusion can be drawn that the pentamethyl HALS series has a higher stabilizing effectiveness than that of the tetramethyl HALS series. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 69: 2649–2656, 1998     

不同受阻胺光稳定剂改性聚丙烯耐光老化性能研究

分析了4种受阻胺光稳定剂在聚丙烯(PP)加工过程中的热稳定性,并研究其单一和复合使用对PP其光稳定性能和力学性能的影响。以失重率为10%时的热分解温度衡量受阻胺光稳定剂的热稳定性,结果表明,受阻胺光稳定剂的加入,使PP的光稳定性能增强;高低分子量受阻胺复合使用,可降低PP的黄变因数和羰基指数,增加其拉伸强度及冲击强度保持率;GW622、GW944和Tinuvin144复合使用效果最佳。     

受阻胺光稳定剂的研究进展

综述了国内外受阻胺光稳定荆（HALS）的研究现状与发展趋势,指出该领域正向高相对分子质量化、多功能化、低碱化、反应性方向发展。并提出了国内HALS产业发展的一些建议。     

新型聚丙烯稳定化体系的应用研究

通过与常规受阻胺类光稳定剂Tinuvin622、Chimassorb944的对比配方实验，考核了复合型光稳定剂BW-6911对聚丙烯的光稳定化效果及耐热氧老化协同效应，建立了新型聚丙烯稳定化体系。     

受阻胺光稳定剂(HALS)在聚合物材料上的应用

介绍了受阻胺光稳定剂(HALS)的稳定机理.讨论了其他稳定剂对其光稳定效果的影响.实验表明:HALS单独使用耐候性不佳,与其他稳定剂复配使用可得较好的结果.此外,一些HALS还能改善聚合物材料的阻燃性能.     

Preparation of antimicrobial sutures by preirradiation grafting of acrylonitrile onto polypropylene monofilament. III. Hydrolysis of the grafted suture

Polypropylene‐grafted‐polyacrylonitrile (PP‐g‐PAN) sutures were prepared by graft polymerization of acrylonitrile onto polypropylene (PP) monofilament using a preirradiation method. The grafted PP monofilaments were subsequently hydrolyzed to introduce carboxyl groups for antimicrobial drug immobilization. The maximum conversion of nitrile groups into carboxyl groups was limited to about 62% and produced sutures with carboxyl content ranging from 0.042 to 0.25 mmol/g. The physical characteristics of sutures were evaluated by FTIR, X‐ray diffraction, differential scanning calorimetry, and X‐ray photoelectron spectroscopy. In general, the hydrolysis did not cause any significant variation in crystalline structure. The mechanical strength was affected in all the grafted sutures. The tensile strength of sutures was investigated as a function of the degree of grafting. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2509–2516, 2004     

聚丙烯纤维阻燃剂应用研究进展

绍了聚丙烯(PP)阻燃剂的种类及其在PP纤维中的应用。PP阻燃剂有含磷、含卤、含硅、金属氢氧化物及其氧化物以及纳米复合材料;讨论了阻燃剂的性能和提高阻燃效果的方法;提出新型阻燃剂必将朝着无卤、消烟的复合型阻燃剂方向发展     

Chemical modification of polypropylene fibers grafted vinyl imidazole/acrylonitrile copolymer prepared by gamma radiation and its possible use for the removal of some heavy metal ions

The chemical modification of polypropylene (PP) fibers by graft copolymerization with vinylimidazole (VIm) and acrylonitrile (AN) was carried out using γ‐radiation. Preparation conditions, such as irradiation dose, comonomer concentration and composition and type of solvent, affecting the degree of grafting were investigated. The suitable diluent for obtaining reasonable graft VIm/AN copolymer yield was acetone. The higher grafted yield was achieved by increasing the amount of vinylimidazole in comonomer feed solution as well as irradiation dose. The derivatives of PP‐g‐P(VIm/AN) grafted fibers of different functional groups were obtained by treating the grafted fibers with various organic reagents containing reactive amino groups, such as sulpha‐drug compounds, aliphatic‐ and aromatic amines. Characterization of the obtained graft copolymers and their chemical treatments with different amines was also investigated. It was observed that the nitrile group in PP‐g‐P(VIm/AN) polymer undergoes simple addition reaction via nucleophilic interaction mechanism to produce the corresponding PP‐graft‐P(vinylimidazole/acrylomidine) derivatives. The ability of the grafted fibers and their treated forms to absorb some metal ions as Cd, Hg, and Pb from their individual and mixture solutions was evaluated. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009.     

杯芳烃、受阻胺及其复合稳定剂对PP的抗光氧稳定作用

烷基取代哌啶胺化合物与三聚氯氰分步缩合反应，合成了中间体6-氯-2，4-双（2，2，6，6-四甲基-4-烷基取代哌啶胺）-1，3，5-三嗪，此中间体再与烷基多胺如乙二胺，二乙烯三胺等缩合得到一系列单体型高相对分子质量哌啶三嗪类化合物；制备了对叔丁基杯[4]芳烃，高分子受阻胺类化合物和PP共混体系，通过老化性能实验评价了共混体系的抗光氧性能，结果表明，杯芳烃，受阻胺类复合稳定剂能明显提高PP的耐光氧性能，且杯芳烃和受阻胺分子间具有明显的协同效应。     

成核剂对聚丙烯辐照交联行为的影响

系统研究了聚丙烯的辐照交联行为,证明加有成核剂的聚丙烯辐照稳定性好,容易制成性能优异的辐照交联聚丙烯。根据此研究结果,发明了“高性能辐照交联聚丙烯的制备”这一专利技术。此技术在化工、建筑等方面均有广泛的应用前景。     

聚合型受阻胺光稳定剂在温室覆盖薄膜中的应用研究

以聚合型受阻胺光稳定剂Uvinul 5050H为主，辅以新型抗氧剂AOD组成农用聚乙烯（PE）棚膜防老化体系。大田应用实验表明，该体系的耐候性能优异。其中采用0．3％Uvinul 5050H的60μm厚PE单层薄膜能够在大田应用12个月以上；含0．3％Uvinul 5050H的100μm厚PE单层薄膜能够在户外使用18个月以上。含Uvinul 5050H的园艺玫瑰生产专用膜，在很好的管理和较少使用硫磺熏蒸的条件下能够使用12个月。     

Influence of degree of grafting and grafting temperature on the permeabilities of grafted polypropylene membranes

Polypropylene dialysis membranes were prepared using cobalt-60 gamma radiation to directly graft 2-hydroxyethyl methacrylate (HEMA) onto polypropylene (PP) membranes. The surface structures of both the grafted membranes and the PP membrane were observed by using FTIR–PAS and ESCA methods. The X-ray diffraction diagrams of the PP and PP-g-HEMA membranes indicated a transformation process of the β-form toward the α-form crystallinity with increasing degree of grafting. The SEM data of the membrane grafted under a low grafting temperature showed many spheres of PHEMA embedded in the PP matrix, whose size was well distributed and increased with the degree of grafting. The influences of the degree of grafting and grafting temperature on the permeabilities of PP-g-HEMA membranes toward urea and creatinine were studied in a dialyzer. In all cases, the PP-g-HEMA membrane obtained under higher grafting temperature showed higher permeability toward those solutes. The permeation coefficients of urea and creatinine through the PP-g-HEMA membrane obtained at 59°C were about 10.4 and 28.8 times that through the PP membrane, respectively. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68:83–89, 1998     

Grafting reactions onto poly(organophosphazenes). VI. Thermooxidative stabilization of poly[bis (4-benzylphenoxy)phosphazene] by grafting acrylate polymers containing HALS groups

Poly[bist 4-benzylphenoxy phosphazene] is heated at 200 C in air and the oxidation of the 4-diphenylmethane side substituent to phosphazene-supported benzophenone, benzhydrol, and hydroperoxides is observed. The thermo-oxidative stabilization of the polymer is obtained by light-induced grafting copolymerization of the acrylic acid 2.2.6.6-tetramethyl-piperidin-4-yl ester onto the polyphosphazene substrate. The HALS moieties grafted onto the polyphosphazene films prevent the oxidative modification of the substituents and preserve the polymer against thermal damage. This process, investigated by IR. UV, and EPR spectroscopy, is basically dependent on the amount of HALS groups grafted onto the polyphosphazene matrix and on the composition of the reaction medium used to carry out the grafting process. The comparison between the thermooxidative stabilization process and the corresponding photooxidative stabilization reaction is also discussed.Presented at the 1st Italian Workshop on Cyclo- and Poly(phosphazene) Materials. Lebruary 15–16, 1996, at the CNR Research Area in Padova, Italy.     

Radiation‐induced grafting of pentamethyl hindered amine light stabilizer 1,2,2,6,6‐pentamethyl‐4‐piperidinyl methacrylate onto polypropylene

The γ‐radiation‐induced grafting of 1,2,2,6,6‐pentamethyl‐4‐piperidinyl methacrylate (PMPM) onto polypropylene (PP) was investigated with a simultaneous irradiation technique. The effects of the solvent, dose, monomer concentration, and photoinitiator on the grafting were investigated. The grafting was easier in a benzene solution than in chloroform and acetone solutions. The grafting percentage first increased almost linearly with the irradiation dose until 20 kGy and then increased slowly or remained constant. The grafting percentage increased with the monomer concentration until 1.1 mol/L. The grafting percentage was higher when the proper amount of benzophenone was added. The grafted samples were characterized with Fourier transform infrared spectroscopy and thermogravimetric analysis. Carbonyl groups were found on grafted PP samples, and the carbonyl index increased with the grafting percentage. Thermogravimetric analyses proved the existence of grafted materials on PP, and grafted PMPM thermally decomposed at a lower temperature than PP. The radiation resistance of PP with grafted PMPM was better than that of pristine PP. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2157–2164, 2005     

我国聚丙烯市场研究

阐述了我国聚丙烯市场的供应、消费状况及其市场结构变化，分析了聚丙烯市场的价格变化规律，综合论述了我国聚丙烯工业在加入WTO所面临的机遇与挑战，提出了我国聚丙烯工业的发展建议。     

受阻胺类光稳定剂改性文物保护材料B72

为了提高B72文物保护材料的耐光性能,采用HALS-622等6种受阻胺光稳定剂对丙烯酸类文物保护材料B72进行改性。结果表明,HALS-5060稳定剂在添加后及老化过程中颜色明显变黄,不宜用作B72改性材料。高相对分子质量(简称分子量,以下同)受阻胺HALS-622、HALS-944比低分子量受阻胺HALS-480、HALS-508和HALS-292稳定效果好,尤其是低碱性的HALS-622受阻胺。因此,采用高分子量、低碱性的受阻胺改性B72是延长其使用寿命、对文物进行有效保护的新途径。     

Sulfonation of (glycidyl methacrylate) chains grafted onto nonwoven polypropylene fabric

Sulfonation of polyglycidyl methacrylate (PGMA) chains grafted onto nonwoven polypropylene fabric is investigated in detail. Sulfonation reaction consists in implantation of sulfonate groups via epoxy ring‐opening of PGMA chains grafted onto nonwoven polypropylene fabric by reaction between the GMA‐grafted sample and sodium hydrogensulfite in water–dimethylformamide solution. On the basis of analyses of IR spectra of the appropriate samples and data of backward titration, two simultaneous processes are demonstrated to take place during the sulfonation reaction. These processes are the implantation of sulfonate groups via opening of the GMA epoxy rings and hydrolysis of the GMA epoxy rings with α‐glycol groups formation. The main peculiarities of the sulfonation reaction in depending on the GMA grafting degree are reported. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

甘油锌及其复合光稳定剂对PVC的光稳定作用研究

对甘油锌用作PVC光稳定剂的光稳定作用进行了研究,考察了PVC紫外光老化后力学性能和颜色的变化。结果表明,甘油锌对PVC具有明显的光稳定作用,与受阻胺光稳定剂Tinuvin770复配,具有明显的正协同效应,当二者的质量配比达到2∶3 时,对PVC的光稳定效果最佳。     

受阻胺光稳定剂的生产与研究进展

介绍了国内外受阻胺光稳定剂（HALS）的生产状况,包括HALS的主要系列、品种、产量和需求情况。阐述了HALS的研究现状与发展趋势,指出该领域正向高相对分子质量化、多功能化、低碱化反应性方向发展,并提出了国内HALS产业发展的一些建议。     

Preparation of adsorbent for palladium ions by amination of acrylonitrile grafted polypropylene nonwoven fabrics

A new chelating fabrics are synthesized by radiation induced grafting of acrylonitrile (AN) onto polypropylene nonwoven fabrics (PP fabrics) and subsequent conversion of cyano to an imine by reaction with ethylene diimine (EDA). Influence of various parameters such as initial concentration, pH and adsorption time on the adsorption amount for palladium ions was investigated. It was found that adsorbent achieved excellent adsorption performance in palladium ion removal in the pH range of 1.88–5.70. The adsorption amount of ions increased with shaking time and initial concentration of palladium ions. The grafted and aminated fabrics were characterized by FT‐IR, TGA and SEM. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010