水表PMMA字轮盒热流道注塑模具设计

通过对水表PMMA字轮盒的结构和成型工艺分析，设计了其热流道注塑模具的总体结构。并详细介绍了热流道系统的结构和先复位机构。采用该模具成功实现了以热流道形式对字轮盒进行大批量自动化生产。     

赫斯基：全新热流道技术闪亮登场

作为热流道和模具生产领域的领先注塑供应商，赫斯基将在K2007展会期间，展出整套热流道和模具解决方案，这是赫斯基在此次展会上亮相的所有革新性产品及服务中堪称重量级的内容。[第一段]     

热流道系统的设计和喷嘴的选择

近年来，为了生产大型或大批量的塑料制品，模具设计师越来越多地应用热流道技术。注塑模的生产企业与热流道专业公司合作完成热流道注塑模的设计与制造，已经取得丰硕成果，提高了注塑件的质量。[编者按]     

热流道系统的设计和喷嘴的选择

近年来，为了生产大型或大批量的塑料制品，模具设计师越来越多地应用热流道技术。注塑模的生产企业与热流道专业公司合作完成热流道注塑模的设计与制造，已经取得丰硕成果，提高了注塑件的质量。[第一段]     

Mastip热流道系统在注塑模具中的应用

1概述 近年来，热流道技术在中国逐渐推广，这很大程度上是由于我国出口到欧美的模具量快速增加带来的结果。在欧美国家，热流道技术已广泛应用于注塑生产中。可以这样说，没有使用热流道技术的模具现在已经很难出口，这种先进技术带来的市场竞争压力也就提高了很多国内模具厂家应用热流道技术的积极性。     

Mastip热流道系统在注塑模具中的应用

近年来，热流道技术在中国逐渐推广，这很大程度上是由于我国出口到欧美的模具量快速增加带来的结果。在欧美国家，热流道技术已广泛应用于注塑生产中。可以这样说，没有使用热流道技术的模具现在已经很难出口，这种先进技术带来的市场竞争压力也就提高了很多国内模具厂家应用热流道技术的积极性。     

移动硬盘盒精密热流道注塑模具设计

热流道注塑模具在模具行业中的应用越来越广泛,采用热流道系统不仅可以保证塑件质量、提高材料的利用率,还能显著提高塑件的生产效率。通过对移动硬盘塑料件的结构及成型工艺特点进行分析,设计了移动硬盘塑料件热流道注射模具,重点对热流道模具热平衡计算和热流道浇注系统进行了分析计算,模具采用单点热流道、一模两件潜伏式浇口、外滑块抽芯机构及斜推杆抽芯成型倒扣设计。实践证明,该移动硬盘塑料件模具设计结构合理,在提高塑料件成型质量的同时,提高了材料的利用率及生产效率,为同类结构特点的热流道注塑模设计提供了参考。     

复杂造型PMMA系列把手通用热流道模具模型研究

针对透明复杂造型聚甲基丙烯酸甲酯把手系列产品,提出采用热流道模具代替冷流道模具注射成型,共用热流道系统,对模架、镶件和铍铜型芯冷却装置等进行模块化组合,建立了把手系列产品的热流道注射成型模具的通用结构模型,满足把手系列产品品种多、表面质量要求高、价格低、成型周期短等要求。并选择一种典型把手进行热流道模具注射成型工艺CAE分析和生产验证,结果符合实际生产要求。     

热流道技术特点分析

热流道模具在当今世界各工业发达国家和地区均得到极为广泛的应用。这主要因为热流道模具拥有如下显著特点:(1)缩短制件成型周期因没有浇道系统冷却时间的限制,制件成型固化后便可及时顶出。许多用热流道模具生产的薄壁零件成型周期可在5秒钟以下。(2)节省塑料原料在纯热流道模具中因没有冷浇道,所以无生产废料。这对于塑料价格     

热流道注射模热流道板的膨胀补偿机构设计

热流道模具的一个重要问题是热流道板加热之后要发生明显的热膨胀，使工作时喷嘴的中心线与常温时的喷嘴中心线产生明显的偏心距，在模具设计时，如果不能在结构上采取措施予以补偿，将使模具变形、破坏或发生其它问题。本文总结了在生产实际中几种可靠的补偿偏心距的结构，对于热流道模具的设计具有一定的借鉴意义。     

差示扫描量热法测定塑料的氧化诱导时间和氧化诱导温度

修改采用ISO 11357:2008《塑料—差示扫描量热法(DSC)第6部分:氧化诱导时间(等温OIT)和氧化诱导温度(动态OIT)的测定》,制定我国相应的国家标准GB/T 19466.6-2009。国内共有13个主要的塑料产品生产厂家和科研单位参加了标准的制定和验证试验工作。该标准的制定填补了我国采用DSC法测定塑料氧化诱导时间(等温OIT)和氧化诱导温度(动态OIT)的空白。     

氧化诱导期法评价聚烯烃原材料的热稳定性

介绍了氧化诱导测试方法,探讨了聚烯烃材料氧化诱导期的影响因素,总结出了温度、流量对其稳定性的影响规律。     

A Commonly Used Biocide 2-N-octyl-4-isothiazolin-3-oneInduces Blood–Brain Barrier Dysfunction via Cellular Thiol Modification and Mitochondrial Damage

Isothiazolinone (IT) biocides are potent antibacterial substances commonly used as preservatives or disinfectants, and 2-n-Octyl-4-isothiazolin-3-one (OIT; octhilinone) is a common IT biocide that is present in leather products, glue, paints, and cleaning products. Although humans are exposed to OIT through personal and industrial use, the potentially deleterious effects of OIT on human health are still unknown. To investigate the effects of OIT on the vascular system, which is continuously exposed to xenobiotics through systemic circulation, we treated brain endothelial cells with OIT. OIT treatment significantly activated caspase-3-mediated apoptosis and reduced the bioenergetic function of mitochondria in a bEnd.3 cell-based in vitro blood–brain barrier (BBB) model. Interestingly, OIT significantly altered the thiol redox status, as evidenced by reduced glutathione levels and protein S-nitrosylation. The endothelial barrier function of bEnd.3 cells was significantly impaired by OIT treatment. OIT affected mitochondrial dynamics through mitophagy and altered mitochondrial morphology in bEnd.3 cells. N-acetyl cysteine significantly reversed the effects of OIT on the metabolic capacity and endothelial function of bEnd.3 cells. Taken together, we demonstrated that the alteration of the thiol redox status and mitochondrial damage contributed to OIT-induced BBB dysfunction, and we hope that our findings will improve our understanding of the potential hazardous health effects of IT biocides.     

单翼迷宫式滴灌带抗热氧老化性能的影响研究

单翼迷宫式滴灌带产品新国家标准中增加了氧化诱导时间（OIT）,这对产品的抗热氧老化性能提出了要求。本文从滴灌带配方出发,讨论了产品原料与其OIT的料效关系,结果表明,防老化母料的加入比例对滴灌带的OIT影响最大,增加其比例可增大滴灌带的OIT;高密度聚乙烯（PE?HD）的加入比例对滴灌带的OIT影响大于线性低密度聚乙烯（PE?LLD）和低密度聚乙烯（PE?LD）的加入比例,增加PE?HD比例、减小PE?LLD和PE?LD比例可增大滴灌带的OIT;PE?LD的加入比例对滴灌带OIT的影响最小,在配方设计时应综合使用比例合理的PE?HD、PE?LLD、PE?LD以满足滴灌带良好的加工和其他性能要求;防老化母料中稳定剂比例不应随成本而减少,稳定剂比例增大时,滴灌带的OIT增大;通过对滴灌带的熔体质量流动速率（MFR）、炭黑含量及OIT指标测试,得出滴灌带MFR和炭黑含量与其OIT无明显的相互变化关系。     

Processes to enhance the sensitivity of sensor for 2-n-octyl-4-isothiazolin-3-one as biocide

In this study, hydraulic treatment was performed to fabricate porous cellulose acetate (CA) membranes for application as adsorbents for impurities. For this purpose, porous CA membranes were prepared by applying a water pressure of 8 bar on CA dissolved in a mixed solvent of acetone and water. These porous polymers could separate impurities from 2-n-octyl-4-isothiazolin-3-one (OIT) by providing adsorption surfaces for the suspended impurities and allowed pure OIT to filter through the membrane; the filtered OIT may subsequently be used for octyl-group quantification. After impurity adsorption, the degree of OIT permeation in the CA membrane and the adsorption mechanism of CA were investigated by Fourier transform infrared spectroscopy and water-adsorption studies. Further, we analyzed the porous characteristics and behavior of CA by scanning electron microscopy and conducted thermogravimetric analysis to observe the physical and chemical changes occurring in the polymers.     

A Novel Method for Determination of the Concentration of Active Antioxidant in Stored HTPB-Based Composite Propellants

The aim of this work has been to find a simple, non-destructive method for determination of the concentration of active antioxidant in HTPB/AP composite propellants. Differential Scanning Calorimetry(DSC) was used for determination of Oxidation Induction Time(isothermal OIT) and Oxidation Induction Temperature(dynamic OIT) at different antioxidant concentrations. The ammonium perchlorate content in the propellants were 80% by weight. The antioxidant was BKF with concentration up to 2.5% by weight of the polymer. Iron oxide was added to some of the samples, and to one of these samples aluminium was also added. The results show that the dynamic OIT depends on the active antioxidant concentration, and useful calibration curves were obtained for the propellants with and without iron oxide. Concentrations of active BKF up to 1.5% by weight of polymer could be determined using this method. Aluminium content in the propellant had no effect on the results. The results also indicate that the isothermal OIT cannot be used for determination of the active antioxidant concentration.     

氧化诱导期法探讨滴灌带的热氧稳定性

通过氧化诱导期方法研究了内镶贴片式滴灌带的热氧稳定性,探讨了滴灌带在加工过程中的降解反应及其影响因素,考察了温度、氧气流量对滴灌带氧化诱导期的影响,结果表明,随温度及氧气流量的增加,滴灌带的氧化诱导期呈现下降的趋势。     

Improving thermo‐oxidative degradation resistance of bamboo fiber reinforced polypropylene composite with antioxidants. Part I: Screening of antioxidants

In this study, the effect of antioxidant application (applied in different combinations, ratios and contents) on the thermo‐oxidative degradation resistance of bamboo fiber polypropylene composites (BFPCs) were investigated, with oxidative induction time (OIT), weight loss, surface color, and flexural mechanical properties as the main indicators for evaluation. The results showed the addition of antioxidants could greatly increase the OIT and reduce the weight loss and color change of the composites after 900 h of thermal weathering. Meanwhile, the flexural mechanical properties were little affected or even slightly improved. The combination of 1076 and DLTP antioxidants at a ratio of 2:1 and 0.2 wt % content was found to exhibit the best thermal oxidation resistance with respect to the OIT, mechanical properties and cost. Our study indicate that the OIT can serve as a simple and quick indicator for the evaluation of thermo‐oxidative resistance of BFPC. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44198.     

DSC加速老化试验方法在PP寿命估算中的应用

利用差示扫描量热(DSC)加速老化试验方法,以不同温度下测得的氧化诱导时间(OIT)为基础,建立温度–寿命相关的阿伦尼乌斯方程,并以此对不同温度下聚丙烯的寿命进行快速估算。结果表明,其估算结果有效,是筛选抗氧剂配方的一种较好的方法。     

无规共聚聚丙烯管材氧化诱导时间测试探究

以无规共聚聚丙烯（PP?R）管材为研究对象，采用差示扫描量热仪（DSC）测试了PP?R管材的氧化诱导时间（OIT），并研究了测试部位、样品直径、样品厚度以及取样方式等测试条件对OIT测试结果的影响。结果表明，从垂直管壁方向取芯层直径为6 mm、厚度为650 μm的试样进行测试时，OIT测试结果相对可靠。