纤维增强聚双环戊二烯的研究进展

综述了纤维增强聚双环戊二烯(PDCPD)复合材料近年来的研究进展。简单介绍了单体双环戊二烯(DCPD)聚合反应、PDCPD性能及其应用,重点讨论了碳纤维、聚乙烯纤维、芳纶纤维、碳纳米管及玻璃纤维增强PDCPD材料的国内外研发情况。最后,对有关纤维增强PDCPD材料的发展趋势进行了展望。     

聚双环戊二烯反应注射成型研究—聚双环戊二烯的合成研究

以ＷＣｌ５／ＷＯＣｌ４．为催化剂，ＡｌＥｔ３为活化剂，在温度为７０～１００℃的条件下采用ＲＩＭ方法完成了双环成二烯的聚合反应．考察了催化剂用量、活化剂用量、反应温度对上述反应的影响，并对聚合物的ＩＲ谱图进行了研究，测定了聚合物中Ｃ＝Ｃ键的含量．实验结果表明．双环戊二烯的聚合反应是一易位开环反应．     

聚双环戊二烯耐腐蚀性能研究

为了拓展聚双环戊二烯(PDCPD)材料的应用潜力,利用溶剂浸泡法研究PDCPD材料的耐腐蚀性能。结果表明：PDCPD材料能够耐受大多数极性有机溶剂、酸碱溶液的腐蚀,但在部分强氧化性的浓酸中,PDCPD分子结构的不饱和CC双键易被氧化,导致材料被腐蚀;由于相似相溶原理,在部分非极性和弱极性有机溶剂中,PDCPD材料会发生溶胀腐蚀,造成材料性能下降。     

改性聚双环戊二烯在免充气轮胎中的应用潜力探究

针对免充气轮胎对弹性体材料的需求,对聚双环戊二烯（PDCPD）采用不同改性方式,制备互穿网络、高交联、聚氨酯接枝改性3种改性PDCPD。改性PDCPD的拉伸模量、弯曲强度、抗冲击强度、耐温性能等都得到提高,在免充气轮胎的轮辐等部件中有一定应用潜力。     

反应注射成型聚双环戊二烯研究进展

聚双环戊二烯是采用反应注射成型工艺合成的一种性能优良的新型工程材料,是通过开环易位机理形成的聚合物。综述聚双环戊二烯聚合机理,反应注射成型技术概况。主要对在运用此技术合成不同类型聚双环戊二烯中采用的不同催化剂体系的作用进行了阐述。     

双环戊二烯改性不饱和聚酯树脂的合成研究

叙述了用双环戊二烯（ＤＣＰＤ）合成不饱和聚酯树脂的新技术,讨论了工艺条件的控制,影响因素及产品性能。工业试验表明,该工艺路线简单,合成的不饱和聚酯树脂与通用型树脂相比,耐热性能好,固含量高,收缩率低,其他性能不低于通用型不饱和聚酯树脂,具有一定的经济效益。     

聚双环戊二烯RIM制品的除臭技术

概述了聚双戊二烯ＲＩＭ制品的优异性能及用途，介绍了国外该制品的除臭技术。     

双环戊二烯改性不饱和聚酯树脂研究进展

较详细地介绍了双环戊二烯改性不饱和聚酯树脂的机理、合成路线(初始法、半酯化法、酸酐法、后期法、封端法和水解法)及国内外双环戊二烯改性不饱和聚酯树脂在气干性、低苯乙烯挥发、低收缩性与力学性能方面的研究进展,提出了今后的研究方向。     

聚双环戊二烯反应注射成型最新进展

可经反应注射成型得到的聚双环戊二烯是一种新型的高性能抗冲工程塑料，其由于原料易得、成型工艺先进、聚合产品性能优异得到了广泛关注。本文就聚双环戊二烯的聚合机理、成型工艺、催化体系、产品性能及应用领域、发展方向做一简单介绍。     

聚双环戊二烯反应注射成型发展概况

简要介绍了聚双环戊二烯反应注射成型的发展概况、性能、加工特点及应用现状。同时进行了经济评价和应用展望。     

Surface modification of polythiophene and poly(3‐methyl thiophene) films by graft copolymerization

Polythiophene (PTH) and poly(3‐methyl thiophene) (PMT) films were electrochemically polymerized in an electrolyte solution of boron fluoride–ethyl ether. Ozone‐pretreated PTH and PMT films were subjected to UV‐light‐induced graft copolymerization with different monomers, including poly(ethylene glycol) monomethacrylate, acrylic acid, and glycidyl methacrylate. Surface grafting with the hydrophilic polymers gave rise to more hydrophilic PTH and PMT films. The structure and chemical composition of each copolymer surface were studied by X‐ray photoelectron spectroscopy. The surface grafting with the hydrophilic polymers resulted in a more hydrophilic PTH film. The dependence of the density of surface grafting and the conductivities of the grafted PTH and PMT films on the ozone pretreatment was also studied. A large amount of the grafted groups at the surface of the PTH and PMT films remained free for further surface modification and functionalization. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis and characterization of macromolecular surface modifier PP-g-PEG for polypropylene

A novel macromolecular surface modifier, polypropylene-grafted-poly(ethylene glycol) copolymer (PP-g-PEG), was synthesized by coupling polypropylene containing maleic anhydride with monohydroxyl-terminated poly(ethylene glycol). The effects of the reaction condition on the graft reactions were studied. The copolymers were characterized by IR, ¹H NMR, thermogravimetry (TG) and differential scanning calorimetry (DSC). The results indicated that the graft reactions were hindered by increasing the molecular weight of PP or PEG. The graft copolymer was found to have a higher initial thermal degradation temperature and lower crystallization capacity as compared with pure PP, and the side chain of PEG hindered the PP chain from forming a perfect β crystal. The thermal stability of PP-g-PEG decreased with the increasing content or molecular weight of PEG. The copolymers were blended with polypropylene to modify the surface hydrophilicity of the products. The results of attenuated total reflectance FTIR spectroscopy (ATR-FTIR) showed that PP-g-PEG could diffuse preferably onto the surface of the blends and be suitable as an effectual macromolecular surface modifier for PP. __________ Translated from Acta Polymerica Sinica, 2007, (2): 203–208 [译自:高分子学报]     

Maleic anhydride based copolymer dispersions for surface modification of polar substrates

In this article, we report the modification of poly(styrene-alt-maleic anhydride) (PSMA) with monofunctional amine-terminated poly(dimethyl siloxane) (PDMS–NH₂) by thermal imidization, followed by the preparation and characterization of a surfactant-free artificial latex thereof and application of this latex onto cotton fabric. The imidization reaction was monitored by NMR and attenuated total reflection Fourier transform infrared (ATR–FTIR) spectroscopy. 1,2-Cyclohexyldicarboxylic anhydride was chosen as a model compound for the PSMA copolymer; this allowed a more detailed characterization by NMR and ATR–FTIR spectroscopy. After the PSMA/PDMS–NH₂ imidization reached completion, a fraction of the anhydrides were ammonolyzed. In this way, a self-emulsifying latex with an average particle diameter of approximately 145 nm and a ζ potential of −56 mV was obtained. It was found that the PDMS-modified PSMA latex in which 30 mol% of the initial amount of anhydride groups were previously imidized by using PDMS-NH₂ and a fraction of the anhydrides were ammonolyzed with 0.3 eq. of NH₃ (PSMA30) was stable in the pH range 4–10. The water contact angle values of the latex-coated cotton textile fabric indicated a hydrophobized surface, with a static contact angle of 135.7°± 1.2°. The washing studies with a standard soap solution of the cotton samples with or without crosslinker showed that the crosslinked PSMA30 offered a good coating durability to the cotton. This waterborne resin based on surfactant-free latices displayed promising properties for coating applications and seemed to be very suitable for the hydrophobization of polar surfaces. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Cotton fabric graft copolymerization using microwave plasma. II. Physical properties

Microwave plasma treatments were applied to lightweight cotton fabric with oxygen, nitrogen, and argon at various microwave power levels and exposure times. The results showed significant effects from the type of plasma, microwave power, and treatment time on the fabric weight loss. Oxygen plasma treatment generates higher weight loss than argon plasma and nitrogen plasma. The breaking strength of the treated fabric was affected mainly by longer exposure time to the plasma. The active centers created within the cellulose macromolecules were used to initiate copolymerization reactions with the vinyl laurate monomer [CH₃(CH₂)₁₀COOCH?CH₂]. The grafted cotton fabric showed excellent water repellency properties. Repeated home laundering of the treated cotton fabrics revealed no significant effect on the water contact angle or on the quantity of grafted vinyl laurate monomer as determined by universal attenuated total reflectance Fourier transform IR, demonstrating the good durability of the treatment that was applied. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 896–902, 2005     

Surface modification of natural rubber film by UV‐induced graft copolymerization with methyl methacrylate

Methyl methacrylate (MMA) was directly grafted on natural rubber (NR) or sulfur prevulcanized (SP) NR surface. The rubber sheet was primarily treated with argon plasma, followed by exposure to air for generating active functional groups. After immersing in a mixture of 30% hydrogen peroxide and MMA in ethanol and water (1 : 1), the MMA grafting took place after UV‐irradiation for 30–120 min. Results from the contact angle measurement and attenuated total reflection–Fourier transform infrared (ATR‐FTIR) spectroscopy showed that the highest amount of MMA grafting was achieved when using 13 wt % of MMA and UV irradiation time of 60 min. The tensile strength and percentage elongation at break of the modified SPNR sheet, having similar MMA grafting to that of NR, were in acceptable range as indicated in the standard glove's test (ASTM D3577). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2270–2276, 2007     

乳酸构型对直接合成聚乳酸-聚乙二醇的影响

直接以左旋乳酸(L-LA)单体和数均分子量为1000的聚乙二醇(PEG)为原料,通过直接熔融共聚法,合成了聚乳酸一聚乙二醇(L-PLEG)。适宜的工艺条件为：以SnO为催化剂[m(SnO),m(L-LA)为0．005],在165℃、70Pa下反应10h。用特性黏数([η])、凝胶渗透色谱(GPC)、差示扫描量热法、X射线衍射、接触角测试等手段对其进行系统表征。L-PLEG的M最高可达0．2056dL/g;GPC测定其重均分子量(Mw为15600;相对分子质量分布为1．30。与以外消旋乳酸(D,L-LA)与PEG熔融共聚合成的D,L-PLEG相比,[η]和Mw较小,而玻璃化转变温度、熔融温度、结晶度较高。     

Modification of polyolefins with silicone copolymers. I. Processing behavior and surface characterization of PP and HDPE blended with silicone copolymers

Permanent surface modification of polypropylene and high‐density polyethylene was obtained by blending with small (0.1 to 5.0% by weight) amounts of silicone copolymers. A triblock polycaprolactone‐b‐polydimethylsiloxane copolymer and a multiblock polydimethylsiloxane–urea copolymer were used as modifiers. Blends were prepared in a twin‐screw extruder. Influences of the type and amount of the additive on the processing behavior and surface and bulk properties of the resulting systems were investigated. During processing, the additives also acted as very efficient processing aids, increasing the extruder output dramatically, up to 200%. Surface characterization by water‐contact angle measurements and X‐ray photoelectron spectroscopy clearly showed the formation of silicone‐rich surfaces even with very small amounts of additives, such as 0.1% by weight. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1625–1634, 2002     

Cotton fabric graft copolymerization using microwave plasma. I. Universal attenuated total reflectance–FTIR study

The effect of microwave plasma on lightweight cotton fabric was investigated. N₂‐plasma, O₂‐plasma, and Ar‐plasma were obtained using a microwave generator at 2.45 GHz under vacuum. The universal attenuated total reflectance–Fourier transform infrared (UATR–FTIR) instrument was used to monitor the changes created after N₂‐, O₂‐, and Ar‐plasma treatments. The exposure of cotton fabrics to the plasma for 240 s with a microwave power of 500 W was sufficient to create active carbonyl groups, as shown by the presence of a peak around 1725 cm^?1 in the FTIR spectra of the treated cotton fabrics. Ar‐plasma was found to generate more active groups than N₂‐ and O₂‐plasmas. The active centers created within the cellulose chains were used to initiate copolymerization reactions with vinyl monomers to impart hydrophobic character to lightweight cotton fabric. The efficiency of the grafting process and the presence of grafted monomers on fabric surface were confirmed using UATR–FTIR. Testing of treated fabric revealed that excellent water repellency was obtained. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 145–154, 2004     

Synthesis of polyimides with low viscosity and good thermal properties via copolymerization

Novel polyimides were successfully synthesized through copolymerization of diamine monomers p‐phenylenediamine (p‐PDA) and 4,4'‐diaminodiphenylmethane (MDA) with different proportions and 2,3,3',4'‐biphenyltetracarboxylic dianhydride (a‐BPDA) using 4‐phenylethynylphthalic anhydride (4‐PEPA) as an end‐capping agent. The melt rheological properties, thermal properties, and crystallinity of PI oligomers were investigated via rheometer, dynamic mechanical analysis (DMA), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and X‐ray diffraction (XRD). The results indicate that melt viscosity and solubility of the PI oligomers were improved, but the glass transition temperature (T_g) and crystallinity decreased with the increasing molar ratio of MDA. PI oligomer 3 with the molar ratio of MDA/p‐PDA = 2/1 shows a lower minimum melt viscosity (66 Pa.s) at 313°C and better solubility in aprotic solvents. The corresponding PI‐3 exhibits a high glass transition temperature of 406°C and excellent thermal stability. This copolyimide shows good processability and thermal properties, and could become a good candidate of matrix resins for high performance composites in aerospace field. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41303.