木塑复合材料型材配方工艺研究

以经处理的不同粒径的木粉和聚氯乙烯(PVC)树脂为主要原料,用双螺杆挤出机挤出生产木塑复合材料型材。探讨了木粉干燥时间和温度、物料的塑化、型材截面对制品成型加工的影响,给出了木塑复合材料型材的加工工艺条件。所生产的木塑复合材料型材具有尺寸变化率小、加热后状态稳定、吸水率小等特点。     

PVC型材发黄的原因

测试了用于生产型材A（合格品）和型材B（颜色发黄）的PVC树脂的原始白度、老化白度、热稳定时间、分子质量及其分布和型材A、型材B的凝胶化度,结果表明：①与型材A相比,用于生产型材B的PVC树脂的原始白度、老化白度、热稳定时间、分子质量及其分布都合格;②型材B外壁的凝胶化度比型材A外壁高约10％,表明挤出型材B时口模处的温度偏高,从而造成型材B表面颜色发黄。另外,还进行了模拟试验,验证了分析结果。     

PVC低发泡型材通过鉴定

由唐山市塑料建材厂研制生产的PVC低发泡型材目前通过专家鉴定。 该厂根据国家轻工产品开发指南和河北省轻工产品开发计划,承担了PVC低发泡型材的研制生产工作。该型材以PVC为主要原材,加入适量的发泡剂、阻燃剂、抗老化剂、避鼠防虫剂等,经混合后采用专用设     

长悬臂铝合金型材开发及应用

本文以L形长悬臂型材为研究对象,对铝合金型材的生产工艺进行探索,总结了长悬臂铝型材熔铸、挤压、时效等生产工序的工艺技术要点。     

PVC彩喷型材自动化生产线的应用

分析了PVC彩喷型材的生产现状，介绍了PVC彩喷型材生产线的组成、特点和使用中的注意事项，对新旧PVC彩喷型材生产线进行了对比。     

型材高速挤出采用水气分离箱的必要性

现在塑料型材已成为化学建材的主力军，但随着产品的推广应用、用户对塑料型材的认可及市场的拓展，型材制造业掀起了一场旷日持久的激烈的市场竞争。加强企业的内部管理、提高生产效率、降低生产成本，在保证自己的最低利润的基础上打价格战已成为各型材生产企业保持自己市场份额的一个重要手段。而目前，型材的高速挤出已越来越成为提高生产效率、降低成本的重要手段。     

影响PVC型材冲击性能的主要因素及原因分析

从聚氯乙烯(PVC)型材生产过程中原料配方、型材断面尺寸、挤出工艺、模具制造等方面分析影响PVC型材冲击性能的因素,并提出了提高型材低温落锤冲击性能的措施.     

中国塑料专利

<正>专利名称:一种PVC石塑型材的生产系统申请公布号:CN204451239U申请公布日:2015.07.08本实用新型公开了一种PVC石塑型材的生产系统,包括混料装置、挤出装置、烫印装置和切割牵引装置。所述型材的顶面为横向呈多个曲面组合的连续曲面组;所述烫印装置为包括若干烫印机的烫印机组;     

浅析真空泵在木塑挤出中的应用

研究了真空泵系统投用对型材挤出制品的力学性能、型材挤出速度的影响及真空泵运行稳定性的影响因素;结果表明:投用真空泵能有效改善型材制品的力学性能,抗冲强度最大提高可达25%,最大载荷最大提高可达26.33%,同时对型材的挤出速度也有一定的提升,型材生产速度最大提高可达33.33%。     

蜂窝结构在PVC-U型材中的应用

PVC-U蜂窝型材,以其独特的断面结构,在保温、隔热、隔音方面优于普通断面型材。本文对蜂窝型材的性能指标、生产中需注意的问题及实际应用中需要解决的问题,进行了较为详细的阐述。     

Protection of ancient and historic bronzes by triazole derivatives

Ancient and historic tin bronzes can be substantially affected by corrosion when submitted to non adequate storage conditions or more aggressive environments such as, for example, the marked increase of air pollution and of acidity of rainwater in urban medium recently affecting outdoor monuments. To protect them, some triazole compounds were tested as corrosion inhibitors of bronze covered with patina layer. As in the case of cultural artefacts, each specimen is unique, an accurate comparison of inhibiting effect of different molecules is therefore hard to realise. To overcome this difficulty, on the basis of a global understanding of the nature of natural bronze patinas, artificial patinas were synthesised on a contemporary bronze (Cu-Sn-Pb) having a similar composition to that of bronze coins dating of the post Roman Empire (5th-6th century AD). Surface characterization and electrochemical experiments were carried out both on contemporary bronze covered with artificial patina and on three ancient bronze coins discovered in Morocco. All triazole derivatives used, benzo-triazole (BTA), amino-triazole (ATA) and bi-triazole (BiTA), exhibited fairly good protective properties on the synthetic bronze. The BTA is efficient in an artificial patina isolated of the substrate bronze and an old bronze specimen covered with patina layer, but this substance is considered as toxic. The BiTA has shown only a slight inhibiting effect on the ancient bronze coin. The ATA is the most effective at 0.1 mM concentration, and the initial treatment of bronze at a higher concentration makes inhibiting effect lower. The ATA is therefore considered the most promising candidate to be applied to protect antique bronze artefacts covered with natural patina layer.     

PTFE复合材料力学性能及摩擦磨损机理的研究

研究了锡青铜粉不同含量的聚四氟乙烯（PTFE）复合材料的摩擦磨损性能,以及添加后对其力学性能的影响,并研究不同润滑介质下的摩擦磨损机理。结果表明：填充锡青铜粉后材料密度增大,邵氏硬度变大,拉伸强度下降;磨损率大幅下降;磨损过程以疲劳磨损为主,在干摩擦条件下伴有磨粒磨损。     

Sr1-xBaxNb2O6钨青铜铁电陶瓷的结构与介电性能研究

通过固相反应法合成了Sr1-xBax Nb2O6(SBN)钨青铜型铁电陶瓷,并对其结构、介电性能进行了系统的研究.结果表明在所研究的成分范围内,SBN陶瓷均形成了四方钨青铜相,但是SBN25陶瓷的主相为焦绿石相,其他3种成分的SBN陶瓷均为四方钨青铜单相.SBN陶瓷均存在一个明显的弥散介电峰,峰值温度随x的增加从室温(SBN25)升高到130℃左右(SBN60);同时峰值温度随频率往高温偏移,为典型的弛豫铁电相变.     

The formation of hydrophobic and corrosion resistant surfaces on copper and bronze by treatment in myristic acid

The surface of freshly etched copper and bronze samples was modified by immersion in ethanol solutions of myristic (tetradecanoic) acid. Modification resulted in the formation of hydrophobic layers with contact angles up to 141°. Two kinds of surface structure were observed. The modified surface of copper was covered by a uniform layer containing nano-grains or knitted-like structure, whereas the modified surface of bronze was covered by a layer with lamellate patterns and nano-grains. The corrosion properties of bare and modified copper and bronze surfaces were tested by potentiodynamic polarization experiments in 0.014 M Na₂SO₄ + 0.024 M NaHCO₃ solution. The deduced effectiveness of corrosion inhibition by the modified layers on copper and bronze was up to 97 and 68%, respectively. Modification of the surface by immersion in an ethanol solution of myristic acid appears to be a promising treatment for improving the corrosion resistance of copper. The same treatment was not very effective when used on bronze.     

甲醇在聚苯胺修饰铂钼共沉积电极上的催化氧化

用恒电位法和循环伏安法在铂电极上分别制备了聚苯胺修饰的分散氢钼青铜电极和分散铂电极,以及聚苯胺修饰的不同铂钼比例的铂与氢钼青铜共沉积电极。用循环伏安法研究了制备电极在c(H2SO4)=0.5mol/L水溶液中的电化学行为,以及对c(CH3OH)=0.1 mol/L的催化氧化行为。其中,分散氢钼青铜电极对甲醇无催化氧化的作用,铂与氢钼青铜共沉积电极对甲醇的催化氧化效果优于分散铂电极。铂-氢钼青铜共沉积电极对甲醇氧化的催化能力与共沉积铂钼的比例有关,当制备电极所用的溶液中n(氯铂酸)∶n(钼酸钠)=2∶1时,共沉积电极对甲醇的催化氧化活性最高,此时甲醇在共沉积电极上的氧化峰电流是单纯铂电极的2.632倍。     

The comparison of organic protective layers on bronze and copper

Copper and its high copper alloys (bronze) tend to passivate in humid air, forming an oxide layer (patina), which protects copper and its alloys from further corrosion processes. Sometimes there is a need to delay or stop further corrosion processes. In this case the surface is protected with natural, synthetic or microcrystalline waxes that are sometimes doped with organic inhibitors, such as benzotriazole. The aim of the present study was to test some organic compounds, including myristic acid and Paraloid B44, as a common finish for bronze sculptures. The mechanism of copper and bronze aging and its influents were determined in a test solution of urban rain.     

改性聚四氟乙烯活塞环专用料研制

研究了青铜粉、玻璃纤维、二硫化钼复合填充改性聚四氟乙烯(PTFE)的力学性能和耐磨性能,结果表明,偶联剂表面处理的方式有效改善了青铜粉与PTFE的相容性;青铜粉、玻璃纤维和二硫化钼的三元协同改性提高了PTFE的耐磨性和硬度,稍微降低了其拉伸强度和断裂伸长率。最终得到了适用于制作中低压压缩机活塞环的改性PTFE的配方(质量含量,下同):青铜粉18%-20%、玻璃纤维10%-12%、二硫化钼5%、PTFE63%-67%。     

中国古青铜器表面富锡铜鎏镀及鎏焊的工艺探索 第三部分──鎏焊

鎏焊是从鎏镀衍生而来的。阐述了鎏焊的定义、特点、应用和意义。设计了用于制作组合青铜器的鎏焊工艺,给出了焊料、焊剂配方,说明了前处理、加热驱汞及后处理的操作方法。以西汉云南纳贡场面青铜贮贝器为例,介绍了鎏镀与鎏焊工艺的具体实施过程。提出了鉴别古青铜器是由失蜡铸造后铸焊而成还是由分铸小件铜焊而成的方法。     

镀锡青铜回火胎圈钢丝生产线

详细介绍了镀锡青铜回火胎圈钢丝生产线，包括镀前钢丝工艺和化镀锡青铜生产线的工艺流程、加工技术参数、设备组成及主要工序。采用此生产线生产的镀锡青铜回火胎圈钢丝性能优良，不仅具备在硫化过程中与轮胎橡胶整体达到良好的粘合的优势，并且具有在轮胎使用中、后期钢丝与橡胶粘合力稳定的特点。     

Uniaxial time‐dependent ratcheting behavior of bronze powder filled polytetrafluoroethylene at room and high temperature

A series of tensile and ratcheting experiments for cold compaction polytetrafluoroethylene (PTFE) and bronze filled PTFE (PTFE/bronze) were conducted with Dynamic Mechanical Analyzer (DMA‐Q800) at room and high temperature (473 K). The effects of peak stress‐holding time, creep, recovery, mean stress history, stress‐rate history, and pretension on the ratcheting behavior of PTFE/bronze were investigated. It is found that longer peak stress‐holding time leads to larger ratcheting strain accumulation. In the meantime, the ratcheting strain accumulates more rapidly at high temperature and the influence of temperature is more obvious than that of the additive fraction of bronze. Creep strain produced during the uploading and the stress‐holding time only partially recovers in the unloading process. Moreover, prior lower stress rate enhances the deformation resistance and restrains the ratcheting of subsequent cycling at higher stress rate. The ratcheting strain in the subsequent cyclic loading at lower mean stress is also restrained by previous cyclic loading at higher mean stress. Finally, the elastic modulus increases and the ratcheting strain is restrained apparently after the pretension. In addition, the elastic modulus and ratcheting strain of the PTFE/bronze with both pretension and recovery are smaller than those with pretension but without recovery. POLYM. ENG. SCI., 54:1571–1578, 2014. © 2013 Society of Plastics Engineers