纸浆模塑制品性能研究进展和发展方向

目前对纸浆模塑制品性能的研究还处在初级阶段,至今没有成熟的测试方法,性能评价标准,以及结构设计理论.对纸浆模塑制品性能研究的进展作了详细的综述,分析了纸浆模塑制品性能研究存在的问题,提出了纸浆模塑制品性能研究的发展方向.     

纸浆模塑制品的缓冲特性

纸浆模塑制品的缓冲特性金潇明译绪言当产品被搬运或运输时，缓冲的作用就是消除或使包装产品由于碰撞和振动造成的损害为最小。一个理想的缓冲系统应提供与产品配合真正需要的或与它所处的环境相适应的保护。例如，多孔聚苯乙烯泡沫用作缓冲材料是非常适合的，因为它具有...     

纸浆模塑制品的结构及分析

随着人们环保意识的增强,纸浆模塑产品逐渐成了包装产品中的宠儿。在我国,纸浆模塑的发展也已经具有一定规模,然而,纸浆模塑制品的结构设计的理论研究方面还很不成熟,制品的设计仍然是经验设计法为多。本文将从容装、缓冲两种结构分析折叠式衬垫,使纸浆模塑的设计方法接近成熟。     

我国纸浆模塑制品的现状和发展前景

纸浆模塑制品是指纸浆经过模塑成型、干燥制得的各种形状尺寸的纸制品。这种制品自30年代投入工业生产以来,现在已具有一定规模。目前全世界纸浆模塑制品产量已达30万吨左右。由于这种制品具有防震性能好、成本低等优点,所以国际市场上广泛用于鲜蛋、水果、玻璃瓶、瓷器、仪器等产品的运输内包装。我国纸浆模塑制品工业化生产发展较晚,过去只有通过手工加工制成的少量纸浆模塑工艺品,真正工业化批量生产是最近几年才发展起来的。我国纸浆模塑制品业的现状     

纸浆模塑制品的用途

当今,纸浆模塑制品正逐步取代发泡塑料制品。纸浆模塑制品以天然植物纤维为原料,其资源十分丰富;制成的各种容器、托盘、护罩、包装等既可降解又可以回收利用,受到广大消费者的青睐。纸浆模塑制品大体有下列几个方面的用途:     

纸浆模塑包装缓冲特性研究进展

1．纸浆模塑制品概述 纸浆模塑制品是用一定浓度的纸浆，加入适量的化学助剂在带有滤网的模具成型机中通过真空或加压的方法使纤维均匀地分布于模具表面，从而具有拟定形状的湿纸模坯，再经过脱水、脱模、干燥和整饰而形成的缓冲包装制品。纸浆模塑技术及其初期产品于1917年在丹麦问世，     

纸浆模塑制品结构强度与缓冲性能综合研究

纸浆模塑制品在环保方面确实具有一定的优势,但在缓冲性能方面与EPS材料还存在着相当的差距.而在一定的条件下,纸浆模塑制品具有替代EPS的潜力.通过对纸浆模塑缓冲衬垫结构上的改进可以改善其缓冲性能.文中主要通过研究纸浆模塑制品抗压能力以及缓冲性能的影响因素来探讨可提高其各方面性能的途径.     

纸浆模塑制品的制造及其应用范围

纸浆模塑制品的制造及其应用范围周高潮ＭａｋｉｎｇａｎｄＡｐｐｌｉｃａｔｉｏｎｏｆＰｕｌｐ－ｍｏｌｄｅｄＰｒｏｄｕｃｔｓ￥ＺｈｏｕＧａｏｃｈａｏＡｂｓｔｒａｃｔ：Ｔｈｅａｕｔｈｏｒｃｅｎｔｅｒｓｈｉｓｃｏｍｍｅｎｔｏｎｔｈｅｍａｋｉｎｇａｎｄｐｒｏｃｅ...     

A design database for moulded pulp packaging structure

In this study, a structural factor approach is developed to allow a modular design method be used for the packaging design of thin‐walled structures. Numerical simulations of the structural units are carried out to evaluate the influence of the structural factors under static loading, by using the commercial finite element code ABAQUS/Explicit. Empirical relations between the load‐bearing capacity of structural units and structural factors are established based on numerical simulations. A database is then constructed that has the ability to provide valuable information for the loading performances of different structural units. Copyright © 2004 John Wiley & Sons, Ltd.     

Compression and cushioning characteristics of moulded pulp packaging

Experiments have been carried out to determine the relationship between the geometry of a moulded pulp packaging and the resulting static and dynamic strength. The influence of the shape of the moulded pulp sample has been examined. The shapes were of rounded and squared geometry, with different draft angles, sample heights, volumetric density in order of the level of hotpressing and surface densities. Static strength was examined by compression test. The experimental results show that cylinders, cones and shapes with large roundings produce better compression strength than squared or rectangular products with small roundings. Dynamic strength was found using drop tests to obtain G curves for first impact of the test samples at different conditions. An equation to determine the maximum G value during the drop was found. The equation shows good correlation to the results achieved for small static loads (the left side of the G curves). C/e curves for the different geometries show that the minimum cushion factor attainable for the tested moulded pulp products is approximately 2.0. Copyright © 2000 John Wiley & Sons, Ltd.     

Development of moulded pulp materials for the packaging of electronic equipment

A new shredded pulp–plastic microsphere composite with modified starch binder which is applicable to the packaging of electronic equipment has been developed. This composite with a 3 wt% microsphere content has almost the same compressive stress at 50% compressive strain as that of (poly)styrene foam, which has a specific gravity of 0.025. A moulded sample of the above composites can be released from a mould after 1.5 minutes of steam heating, the same cycle time as that of styrene foam. © 1997 John Wiley & Sons, Ltd.     

Moulded pulp products manufacturing with thermoforming

For an effective optimization of pulp thermoforming and of the moulded pulp products manufactured by this process, a full understanding of the process physics combined with full knowledge of the pressing equipment is necessary. For this reason, in this Addendum, we clarify how the process parameters “Holding time,” “Vacuum time,” “Cycle time,” and “Temperature” were interpreted and subsequently defined for the analysis of the process and product‐related outputs of the thermoforming experiments.     

Moulded pulp products manufacturing with thermoforming

Over the past years, eco‐friendly packaging solutions such as moulded pulp have resonated with a growing number of consumers. Among all of them, the thermoformed products make use of the most recent manufacturing approach that produces high‐quality, thin‐walled items. However, it remains an underresearched area, and the development of an efficient and precise manufacturing process is fundamental in order to increase the implementation of sustainable packaging. With the purpose of setting a step towards in the standardization of design and testing practices of eco‐friendly packaging, this work focused on the characterization of the thermoforming process of moulded pulp products and their characteristics. Three different analyses were carried out for this purpose, covering the dewatering efficiency of the process, a quantification of the moulding geometrical accuracy, and an analysis of the internal microstructure of the parts. Experimental results and statistical analysis show that the dewatering efficiency is mainly governed by the mould's temperature while the duration of the contact time is not influential. In the second investigation, the geometrical accuracy of the mouldability of microfeatures was assessed. The process appeared to be dependently related to the pulp type employed. Finally, the internal microstructure was documented using X‐ray computed tomography. The analysis shows an increase in the internal void fraction linked with an increase in the mould's temperature. The role of the water change of phase in the thermoforming process is also discussed by reference to the work conducted on impulse drying.     

Multidimensional life cycle assessment on various moulded pulp production systems

Moulded pulp has been used as an alternative to plastic in certain packaging applications, but some problems in the production system lead to higher costs including energy consumption. Industry tends to operate on the basis of experience rather than through scientific evaluation and systematic design methods. The research aims at detecting the problems in the production system by a multidimensional life cycle assessment (MLCA) with transparent analysis. The MLCA measures the performance of the moulded pulp production system with regard to technical, economic and environmental aspects and produces quantitative results (in monetary units), and finally indicates the overall efficiency of the production system using a sustainability index (SI). A life cycle impact assessment method based on endpoint modelling (LIME) is mainly adopted in the MLCA. Three existing moulded pulp production systems for industrial packaging in China were assessed in this study. The results show that the main environmental impacts of the three production systems are the atmospheric emissions and landfill waste; the drying stage in the production systems, which is dominated by consumption of resources and environmental impacts, is the key to controlling costs; steam should be the first preferred heat source in the drying process for achieving sustainability in the moulded pulp production system. The optimum for the three cases is identified by calculating the newly developed SI. The MLCA approach can be used to assist in identifying potential improvements and practical new packaging designs. Copyright © 2009 John Wiley & Sons, Ltd.     

Cushioning properties of moulded pulp

Cushion curves for a moulded pulp material were constructed and compared with cushion curves for an expanded polystyrene (EPS) foam. The ability of the moulded pulp material to provide some shock absorption resulted from a number of ‘dimples’ moulded into the pulp sheet. As an impact was applied to the moulded pulp, these dimples crushed and thereby mitigated the shock. Results showed that the moulded-pulp test samples had good cushioning characteristics for low static loadings, low drop heights, and single impacts. However, the cushioning characteristics of the material were inferior to those of EPS foam at static loadings above about 5kPa, and where higher drop heights or multiple impacts occurred. These properties were improved by using two samples with interlocking dimples. It was concluded that the material had the potential to replace EPS foam in a limited number of situations, and several recommendations for future research were given.     

纸浆模塑制品结构设计

纸浆模制品在产品的包装与固定、产品的缓冲防震应用中,是通过各种结构形式来满足对产品的包装保护要求及使用要求.纸浆模塑产品结构设计影响着纸浆模制品的缓冲性能,影响着对产品的包装要求,因而影响着纸浆模制品的包装结构、加工生产及模具设计与加工方法.     

纸浆模塑制品对流干燥机理及其节能原理

对流干燥是国内纸浆模塑制品生产工艺中主要运用的干燥方法.降低干燥过程的能量消耗是降低生产的成本和保证制品质量的关键.讨论了纸浆模塑制品对流干燥的数学模型,并从能量衡算的角度分析了厢式干燥线纸塑干燥节能的若干技术途径.     

Thermal study of injection moulded ring

Application of CAD/CAM techniques to injection mould design is feasible and required now in view of the low cost of computers and the need to develop moulds in the shortest possible time. For this purpose a simpler thermal analysis of an injection mould is desirable, as most of the mould makers in Asia are in the category of small manufacturing units. This paper presents a thermal model of injection moulds for axisymmetric components using polar co-ordinates. This model could be utilised for studying the shrinkages, thermal residual stresses and cooling channels. A design example is presented to explain the method of application of the developed model.