polymers论文范文

哇！你是哪个学校的？

Precision injection molding technology of progress Abstract: The polymer precision injection molding technology, impact on precision injection molding of factors, including the precision molds, injection molding machine control accuracy, precision injection process control and other computer control technology. These factors were discussed, and give the relevant solutions, finally introduces some advanced molding technology. Key words: precision injection; injection molding machine precision injection technology; Precision Injection Mold In recent years, as electronics, telecommunications, medical, automotive, and other industries of the rapid development of the high-precision plastic products, and high-performance requirements of growing precision molding technology to continue to progress, new technologies continue to emerge. Precision injection molding products not only require high dimensional accuracy, and low warpage, to write good, but there should also be excellent optical properties. Injection molding is the most important one of the plastic molding methods, including plastics plastics, injection, packing, cooling, and some of the basic process, thus affecting the precision injection molding of many factors. 1, precision molds To produce sophisticated products, precision molds is essential. Die Die in general, the accuracy of the temperature control, mold and die design precision manufacturing, use of plastic shrinkage rate impacts. Precision Mold temperature control In general precision injection molding of parts, control mold temperature is to increase productivity. However mold temperature control for precision injection molding of great impact, it affects parts of the contraction, shape, crystallization, such as stress, hot and cold circuit design mold temperature distribution at the request reasonable, precise control accuracy, a die temperature of the best and Lengshuiji control. Mold temperature control and cooling time on the products and their impact on performance of the following factors: (1) melt plastic injection molds and a two-cycle time will be produced in the mold temperature difference fluctuations, and should therefore be to minimize the volatility differential peak. (2) the heat transfer Die Die Die heat through the concrete and die in the transfer out of the media, mold is changed, the media control is the key, the general import and export of its cooling water temperature difference is less than 1 ℃ Application of theory to calculate the average temperature, which can guarantee the stability of heat transfer. Media flow and heat transfer are interlinked, mould surface temperature can be used to control the media flow sensor to compensate for environmental temperature changes caused by mold temperature changes. (3) To enable stable Die Die by the heat absorption and dissemination of balance, the injection molding machine to melt injection to strictly maintain a stable temperature. Die surrounding temperature on the mold had a great impact on the general will be affected to die within the melt convection coefficient of change, so the best set up in the mold surface temperature sensor, die at any time observation of the surface temperature, and keep it stable. (4) changes in the efficiency of heat exchange with mold after a long time in the cooling water pipes and Youban appears in the scale, then the interface to reduce the thermal conductivity should furring timely clearance. Precision Die Design and Manufacture Die design is good or bad is to ensure the dimensional accuracy of plastic parts premise, in order to enhance the accuracy of precision injection mold, in the process of designing a computer-aided analysis is necessary, especially for gating system and the flow of heat-conditioning systems mold temperature distribution the analysis. Applications should be as much as possible the use of simulation software and close to the actual loading conditions to melt in the mold simulation analysis in the pouring, cooling, and other non-steady-state process. Die manufacturing quality assurance plastic parts Size is the key to accuracy, precision die is the main characteristic of the manufacturing and assembly operations in addition to polishing, are no manual processing. Die general machining and manual processing ratio is about 6:4 to 7:3, and the machining precision molds and manual processing ratio of 9:1. Die materials and heat treatment is the protection of precision molds in the molding process, the die temperature in the state, which even the mould parts tempered by low temperature, high temperature melt production and will repeat parts tempering而使lower hardness, Consideration should also be given retained austenite caused by the volume expansion. Therefore general tempering temperature should be at least molding processing, more than double the die temperature and low-temperature processing is carried out properly in order to eliminate residual austenite. On the high-precision products for Molding precision parts, assembly accumulated precision die in the direction of the accuracy of the sub-surface as well as the parallel degree should achieve micron level. Mold should have sufficient strength, stiffness and abrasion resistance, in the injection molding deformation under the pressure of hard wear. To achieve the above processing can be three-dimensional precision machining centers, CNC machine tool and application of CAD / CAM / CAE and other new technologies. precision molds design shrinkage rate of use Thermoplastic plastic molding shrinkage volatile, to mold design, identify and control products cavity size dimensional accuracy difficult. Therefore, in plastic mold design should understand the characteristics and contraction caused by the shape of the parts of the difference in the rate of contraction site, and then use the necessary compensation measures. On the high-precision plastic parts can be manufactured in the design before simple mold, measured molding to the various parts of the actual shrinkage rate, this can greatly enhance the dimensional accuracy of parts. , the design of precision molds gate Gate type, size, location and quantity of all affected parts dimensional accuracy. At the gate of the jet, but the effects of poor feeding, thick-walled parts do not apply. Gate position and the flow of impact melt flow distance, the longer the process of the greater contraction. Multi-gate process can be shortened, but increasing weld marks. Gate parts should be designed in accordance with the size and the choice of materials and the use of software to help finalize practical experience. 2, the best precision injection molding process parameters set Choose the best molding process parameters to reduce plastic shrinkage rate. Plastic is that the contraction of the heat shrinkable plastic, elastic recovery, plastic deformation, contraction after contraction and a comprehensive reflection of aging, usually caused by absorbent material or molecular chain rearrangement caused, the specific performance linear shrinkage rate and volume contraction rate changes in value of common contraction said. Thermoplastic plastic injection molding products shrinkage volatile, particularly for crystalline plastics injection molding products even more obvious, and not only depend on the degree of crystallinity due to the chemical structure, but also by the process of cooling parameters (cooling rate, the melt temperature, mold temperature , product thickness) the impact of the mold cavity size and design determine the size precision control products and difficulties, there is an urgent need to be aware of parameters on the injection molding of plastic shrinkage rate of the impact of the law. Part of the difference in thickness is generally believed that the two factors: First, high-pressure melt the mold cavity caused minor deformation of a die when the elastic modulus material after the expansion. Generally speaking, quality control and accuracy can be very good dimensional accuracy, and at a higher temperature, mold low melt viscosity, viscosity smaller gradient, in a certain screw back pressure, the quality of precision parts can be accurately controlled. But for liquid crystal polymer (LCP), it just needs a lower mold temperature, it is because cold LCP case will be promptly after cooling amorphous. LCP have low melting heat and orderly structure of the state, in the liquid crystalline state to change between crystalline solid, smaller changes, when fully cooling, the liquid - solid transition is almost complete in an instant. Die in the colder, when a cavity, the cavity material and the bulk of gate has been cured, it is very difficult stage compression added melt, thus parts and the size of the cavity size of the deformation is very close. Plastic amorphous than crystalline plastics low shrinkage with a mixture of contraction rate of low-polymer materials, elastomers at the same time as the increase of the content, materials shrinkage rate decrease. The enhanced or plastic filling, heat capacity decrease stiffness increased significantly reduce shrinkage and fiber filler content or higher, the smaller the rate of contraction. Crystalline precision plastic products also affected by pressure. As pressure crystallization of the role of injection pressure (P1), the packing pressure (P2) and the feeding pressure (P3) to speed up the crystallization process, crystallization of the P1, P2, P3, the increase in upward trend. For P1, the pressure to improve the crystallization of the degree of crystallinity, the contraction rate of increase rose P2 and P3, on the one hand because of the degree of crystallinity increased shrinkage rate increase, on the other hand increased to P2 more pressure to melt, the type cavity has been fully compacted plastic; P3-feed increased to increase, and effectively prevent reflux is conducive to reducing shrinkage. Therefore, the plastic parts of the shrinkage rate is the result of both, with the shrinkage of P1, P2, P3, the first increases and then decreases increased. Precision plastic parts requires not only a stable size tolerances, but also requires strict mechanical properties. These characteristics mainly depend on the cooling phase of the melt in the heat - mechanical role of the historical process. Mold temperature and cooling time on the quality of products and have a direct impact on productivity. Study found that, given the die temperature, the dimensional accuracy of products with the cooling time is not the extension has been significantly improved, and only in a certain period of time, after a prominent role. In general cooling process in such a critical point in time there are two cooling, cooling time in the first point although production products also higher accuracy, but it is not the most stable state, and the second point-in-time cooling cooling relatively long time, However, the products enable the most stable state. 3, using precision injection molding machine to replace conventional injection molding machine Precision injection molding machine generally larger injection power, in addition to such injection pressure and injection to meet the requirements in terms of speed, power itself will be on the injection products improve the accuracy of a certain role. Precision injection molding machine control systems generally have high control precision, it is requested by the products themselves. High accuracy can be guaranteed control of injection process parameters has good accuracy, precision products in order to avoid fluctuations due process parameters change. Therefore precision injection molding machine generally of the injection, injection pressure, injection rate and pressure-pressure, back-pressure and screw speed process parameters such as a multi-level feedback control. Precision Injection requirements of its modulus system has sufficient rigidity, accuracy or products will be a model for the elastic deformation decreased. Second-Die-Die of the system must be able to accurately control the size, or too large or too small a model of precision products will have an adverse impact. So in the design, it should be considered Die rigidity, stiffness, as well as a model system in order to accurately control the size of the precision products, especially flat-panel thin-wall products. When Die larger, must-oriented column deflection check. Precision injection molding machine also must be able to work in the hydraulic circuit precise temperature control, work to prevent the oil due to temperature changes caused viscosity and flow changes, further injection process parameters leading to fluctuations而使products would lose their accuracy. parts molding cycle time consistency General typical injection molding machine with three modes: manual, semi-automatic and fully automatic. As the influence of various factors, each of the previous two models molding cycle time may be different, it would affect the temperature and materials to die in the Liaodong stay, thereby affecting the accuracy of parts, in precision Molding should try to use the automatic mode. precision injection molding machine screw temperature control and the design of new Injection Molding Machine cylinder automatic thermostat on the cycle of opening and customs led to the Liaodong, melting material density and viscosity changes, thereby affecting the quality and dimensional accuracy of parts of the cyclical fluctuations in the injection molding machine nozzle close to Die Therefore, the temperature of the nozzle molded parts also have a significant impact on. Modern injection molding machine equipped with a special process control software to control temperature fluctuation, which is proportional integral differential (P ID) control. At least from the barrel temperature difference galvanic point perspective, the P ID parameter optimization can completely eliminate temperature fluctuations. To the quality and stability of the plastic parts, plastics injection molding machine unit is very important. To the plastics unit is an important standard to judge: injection volume, plastics rate, injection rate, the polymers in the plastics unit at the time. As the quality of plastic parts for the dimensional accuracy error of a very important impact, and it should be precise injection control of the injection molding machine. Improve measurement precision injection molding machine of the most effective ways is to use technology to achieve the smallest screw diameter, especially for the light parts especially. The measurement of the relative screw length and the overall length of screw smaller, in the plastics materials unit at the time also become shorter. Screw thread is similar to widening the materials can be avoided stay longer so that the screw and stable operation. Lo deep groove width than correspondingly smaller, which create a lot of engineering plastics parts of the small diameter screw particularly effective. Melt homogeneity and are not small compression ratio decreases, it is because from the very shallow groove Lo caused very strong result of the shear rate. Feeding the difficulty of the design, it must ensure that all aggregates can be fed into evenly. Considering the need to shorter cycles, plastics rate must also be big enough, in the design of the feed must be effectively resolved the contradiction between. In addition, if adopted by a two-stage injection screw to achieve precise control injection error, which requires the measurement of the melt through spherical valve detected by injection to injection molding machine in the Detroit injection molding machine. Before microprocessor controlled by the injection molding process can not be obtained through injection precision voltage comparator has been successfully resolved. Voltage comparator allows Transmitter and other sensitive came with the very precise voltage signal passed, and when the set point appears to be following the true value of a timely signal immediately transmitted to the microprocessor control of the order, by order of the cycle of operational procedures Asynchronous from time to time through a direct transfer of the signal process to eliminate, greatly improving the control accuracy. 4, precision molding technology in the mold injection-compression molding applications (ICM) technology ICM technology is the means to open a certain distance die under the conditions of the beginning injection, injection to a certain amount, the mold cavity beginning of the closure of the melt compression, injection mold completely closed at the termination, and then packing, cooling until the removal products. Through injection-compression molding of compression products to compaction, making products on the surface of uniform pressure distribution, the compaction products such size high accuracy and stability, small deformation. It is in the mould open circumstances melt into the cavity and, therefore, mobile channel, for the low pressure injection molding, and reduce or eliminate the pressure caused by the resin-molecular orientation of the stress and products, which improve products, dimensional stability. ICM technology and flexible control capability than the injection mould has greatly improved. Therefore use of this technology can produce more precision parts, especially the high-precision cylindrical-shaped parts. high-speed injection molding High-speed injection molding method of filling melts faster rate than the traditional 10 to 100 times, melt in the mold cavity to produce high shear flow, decrease viscosity, injection speed, slow down plastic surface hardening, thus improving thin Forming products wall thickness limit, inhibit excessive molding pressure, as well as because of the low-voltage mobile mode, the products reduce stress. The thin-wall precision products, we can use the injection screw at the forward from the melt energy absorption in the screw after the cessation of movement through the expansion of high-speed melt full cavity to achieve. no-pressure injection molding No-pressure injection molding technology refers to the plastic melt high-speed, high-pressure filling into the mold, and then close in the nozzle needle to melt the plastic mold cavity products automatically compensate for different parts of the contract, such products can be greatly reduced warpage. However, this method requires prior estimate packing contraction added, hence the need for the injection of a higher cavity pressure value, and we need clamping force also high. Other Intelligent Control Technology Precision injection molding processing conditions in the process of continuous monitoring and implementation of precise control is very important. With the development of computer technology, computerized injection molding has been widely used. Among them, statistical process control (SPC), P ID technology, fuzzy logic control (FCC), network control center (NNC) method and the processing model based on the reverse of the backbone network size control. 5. Conclusion On the high-precision plastic products, and high-performance requirements of the growing precision injection molding technology is the impetus for moving forward, people on the principle of precision injection molding, the constant deepening of understanding of precision injection molding technology is the basis for progress. With new materials, new processes and new equipment has emerged, particularly in the plastics processing computer is the wide application of the precision injection technology to create good conditions. As long as a reasonable use of these technologies, we will be able to produce sophisticated products.

It's easy but I dont't know what to write so if send the information to me, I can traslated for you!!!~ ^-^

吸水polyaminosiloxane环氧热固性聚合物作者： . Cabanelas ，法国兴业Prolongo湾塞拉诺，学者布拉沃，学者Baselga 摘要：摘要吸水率是一种常见的问题环氧树脂基复合材料，尤其是在界面区域。相反，环氧树脂，有机硅具有疏水性材料。热固性环氧改性有机硅应改善与物理性能，由于减少了水的扩散。双酚A二缩水甘油醚（ DGEBA ）治愈的合成氨perfunctionalised硅氧烷。吸水率分析了不同的技术，包括近红外光谱（ FTIR ）吸水率在五二○○厘米- 1和重量。菲克定律扩散系数进行了计算。溶胀平衡树脂还分析。吸收水触发的固化反应强烈，从而使达到高转换率。 © 2003埃尔塞维尔科学B.诉保留所有权利

polymers期刊范围

polymers是二区期刊。在高分子领域，polymer算是很不错的期刊了，polymers是二区期刊，都是很不错的期刊。《POLYMER》期刊出版来自高分子科学技术各个领域的着重于从分子或介观尺度解释数据的原创性研究，其中特别欢迎来自新兴领域的论文，除了常规的文章和通讯，该期刊也出版综述，通常受编辑邀请。

SCI四区期刊期刊名字 HIGH PERFORMANCE POLYMERS期刊ISSN 0954-0083 2015-2016最新影响因子是否OA开放访问 No 通讯方式 SAGE PUBLICATIONS LTD, 1 OLIVERS YARD, 55 CITY ROAD, LONDON, ENGLAND, EC1Y 1SP 涉及的研究方向化学-高分子科学出版国家或地区 ENGLAND 出版周期 Bimonthly 出版年份 1989 年文章数 107

polychemistry是英国RSC新出的杂志，由于RSC之前没有关于高分子这类的专业期刊，其定位在ACS中macromolecules这样的档次。

Polymer Chemistry 是RSC新出的杂志,由于RSC之前没有关于高分子这类的专业期刊，其目标定位在ACS中macromolecules这样档次，由于新杂志要3年以后才有影响因子，不过其影响因子应该定位在4以上。由于没有影响因子，很多时候审稿没有一个很好的定位和参考，所以目前很多人在往里面灌水，一来可以使工作新意一般的文章发表，二来赌一把，也许影响因子高的话，他们就赚了。对于，RSC的来说，现在很多副编为了宣传心出来的杂志，在对于接收的文章中会向大家宣传并引用这些杂志上发表的文章。

polymers期刊缩写

polymers在我看来一直都是一个不错的期刊，按照影响因子高度划分，polymers期刊属于三区，比一区和而且发表容易一些。在高分子领域，polymer算是很不错的期刊了。

polymers期刊简介

《聚合物》( ISSN 2073-4360)是一本国际性的开放式聚合物科学期刊。它发表研究论文、简短通讯和评论论文。我们的目的是鼓励科学家尽可能详细地发表他们的实验和理论结果。因此，论文的长度没有限制。必须提供完整的实验细节，这样结果才能重现。聚合物为发表论文提供了一个跨学科的论坛，这些论文推进了(I)聚合方法，(ii)理论、模拟和建模，(iii)对新物理现象的理解，(iv)表征技术的进步，以及(v)利用自组装和生物策略生产复杂的多功能结构。

平均审稿速度：网友分享经验：平均17天；

平均录用比例：网友分享经验：较易

国内高分子材料科学与工程高分子通报高分子学报功能高分子学报 Chinese Journal of Polymer Science 国外 ADVANCES IN POLYMER SCIENCE EUROPEAN POLYMER JOURNAL JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY PROGRESS IN POLYMER SCIENCE POLYMER MACROMOLECULES Macromolecular rapid communications POLYMER DEGRADATION AND STABILITY POLYMER INTERNATIONAL POLYMER SCIENCE SERIES C COLLOID AND POLYMER SCIENCE JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS

polymers期刊花钱吗

polymers期刊简介

平均审稿速度：网友分享经验：平均17天；

平均录用比例：网友分享经验：较易

polymers是预警期刊吗

不是的。《CARBOHYDRATE POLYMERS》所属分类：首页 > SCI期刊 > 化学。《CARBOHYDRATE POLYMERS》发布于爱科学网，并永久归类相关SCI期刊导航类别中，只是硬性分析 "《CARBOHYD POLYM》" 杂志的可信度。学术期刊真正的价值在于它是否能为科技进步及社会发展带来积极促进作用。

Polymer Testing 是SCI 索引期刊，也是聚合物测试领域的权威期刊之一，特别是在测试表征领域，该期刊影响力还是很不错的。

不是polymer testing 网络聚合物检测;[例句]The Research of Horizontal Analysis on Exterior Insulation and Finish with Polymer Mortar Adhesive Strength Testing Method外墙外保温用聚合物砂浆粘接强度检验方法的分析研究