I. INTRODUCTION The so-called "new type of buffer packaging material" is a "new type" of methods and concepts. Thanks to human efforts, the innovative ideas of the paper pulp moldings and corrugated cardboard folding buffer structure, as well as the domestic and international products, especially the electronic packaging products, have given us inspiration. Among various kinds of packaging materials, paper products have a relatively small degree of pollution to human society, and in particular, the degree of waste pollution after their products are discarded is relatively small. In this regard, pulp molded products and corrugated cardboard products are used as buffer packaging. The "new materials" also advanced a huge point in the sense of environmental protection. Therefore, we use corrugated cardboard corners made of buffer packing corner pads, and its performance was studied.
As we all know, corrugated paper has a certain buffering properties. Because, it is itself made of pasted paper, core paper, and inner paper (not like single sheets, it is too bent and deformed, and it has no recovery capacity), and contains many "microscopic" air gaps; After corrugated paperboard core paper is bonded, it is not fully tensioned, which is conducive to deformation and absorption of energy when subjected to external force. In addition, the multi-layered constrained structure of corrugated paperboard will still have a shape recovery effect after being subjected to a certain force. We use corrugated board corner material as raw material, which is mainly based on this factor, and it is the trend of complying with waste utilization and green environmental protection.
II. Experimental data and performance analysis of "new type" materials Whether an idea is feasible, and the effect and influencing factors are numerous, sufficient consideration should be given and conclusions drawn from the test data. In fact, there are many influencing factors for such materials, such as cross-cutting and slitting of corrugated cardboard strips; width and width of corrugated cardboard strips; corrugated type of corrugated medium; changes in temperature and humidity; weight of paper, core, and paper; pulp's Raw materials and production process; corrugated board technology; type and amount of adhesives applied; direction of macro-alignment of specimens; degree of damage to smash type, and moisture content of test pieces, etc. However, we have done some experiments on the combination of the limited factors that we have achieved, and we have come up with more ideal conclusions, and have also explored a path for future research and development. As a guide for jade, the following uses cushioned corner pads made of corrugated board blanks and some of the physical properties to give readers necessary explanations.
Contents: single-degree-of-freedom system for plexiglass enclosures;
Corrugated cardboard horizontal and vertical slitting strips: vertical and equal cutting strips;
Density: After selecting the size of the outer box and corner pad, the amount of raw materials is also graded;
Sizing amount: The amount of glue used when molding each corner pad is divided into two levels;
Punching: Add a round hole structure to the corner pad of the sample;
Horizontal and vertical compression: Most of the corrugated paper strips are vertical or equal to the bench when compressed.
In the case of a combination of different factors of the same size, the foam plastic and the new cushioning material are subjected to static compression deformation, impact drop and vibration experiments, and the specific experimental data are compared to analyze and research whether the new buffer packaging material meets or exceeds the polystyrene. Vibration damping performance of ethylene foam.
Through hundreds of comparison experiments, many groups of data have been feared, involving a combination of multiple factors. The experimental process is as follows:
1. Positional compression experiments Through the pressure and deformation characteristics of polystyrene foam and a new type of cushioning material, the compression and elastic resilience tests of the material, and the related calculated values ​​of the material, such as the stress and strain of the material, are further obtained. , absorb energy, and buffer coefficient, etc. Thus, a graph of the cushion coefficient, static stress, etc. of the material is obtained. Some experimental data are summarized as follows:
Single Corner Pad Compression Type Minimum Cushion Coefficient in Current Data Foam (Large) 1.461 Foam (Medium) 1.416 Foam (Small) 1.376 New Material (Large Longitudinal First Compression) 0.927 New Material (Large Longitudinal Second Compression) 0.697 new material (large 45% humidity horizontal) 7.006 new material (large 45% humidity longitudinal) 8.191 new material (large 90% humidity) 1.891 new material (medium hole) 1.973 new material (Medium small glue longitudinal) 1.056 New material (small horizontal) 2.199 New material (small vertical) 1.184
Four Corner Cushion Simultaneous Compression Type Current Data Minimum Buffer Coefficient Foam Plastic (Large) 2.27 Foam (Medium) 2.447 Foam (Small) 1.866 New Material (Large Horizontal Compression) 3.427 New Material (Large Longitudinal Compression) 3.944 New Material ( Large 90% humidity) 2.678 New material (large 45% humidity) 3.225 New material (medium hole) 3.333 New material (medium size) 2.826 New material (medium transverse compression) 2.967 New material (medium longitudinal compression) 1.576 New material (Small) 1.011
2. Impact drop experiment When studying the buffer coefficient of materials, it is indispensable to study dynamic effects. Acceleration sensors are installed in the system to obtain the acceleration values ​​under the experimental conditions. Due to the limitations of the experimental conditions, the surface drop method was used in the simulation. Raise the packaged items and the outer package to a height of 60 to 70 cm to allow them to fall freely. Using a computer to analyze the magnetic recording signal and using a standard signal generator to obtain a standard signal of 1G, a comparison was made between the polystyrene foam packaging and the new cushioning material packaging in the same impact drop situation as follows:
Type Current data Minimum cushion coefficient Foam (large) 2.27 Foam (medium) 2.447 Foam (small) 1.866 New material (medium transverse compression) 3.427 New material (medium longitudinal compression) 3.944 New material (large humidity compression) 2.678 Material (medium hole) 3.333 New material (medium size) 2.826 New material (large size) 2.967 New material (large medium density) 1.576 New material (large small density) 1.011
From the above comparison, it can be seen that the data of the old and new buffered packaging corner pads are very close, and the new buffer packaging material also exceeds the foaming effect of the foam in some places. According to the above comparison of peak values, the average peak value of the small, medium, and large foam samples is 42G or more, and the peak data obtained from the other test samples under the same conditions are also in the same order of magnitude, basically staying at 41.0 to 44.33G. Above, the same effect as the foam cushioning performance is achieved. This fully demonstrates that this idea is feasible, and also proves that this new type of material can fully achieve the purpose of buffering, and can replace foam for the application of cushions.
3. Vibratory Performance Test As a foam packaging foam packaging, it was able to dominate the moment, in addition to a good cushioning performance, vibration absorption performance is also very good. This material has tiny pores and viscoelasticity and absorbs vibrational energy due to viscous damping and air damping during the vibration process. We compared the experimental data of new material corner pads and foamed plastic cushions with various factors after simulating actual packaging. The combination of different experimental parameters under the same experimental conditions gave the maximum transmission rate of each system at resonance frequency. As shown in the table:
Type System Resonance Frequency Minimum Buffer Coefficient in Current Data Foam (Large) 11Hz 4.36 Foam (Medium) 13Hz 4.91 Foam (Small) 12Hz 4.33 New Material (Small) 14Hz 2.84 New Material (Medium Horizontal Compression) 11Hz 3.42 New Material ( Medium-sized Longitudinal Compression 12Hz 3.69 New Material (Large Humidity Compression) 12Hz 3.03 New Material (Medium Hole) 11Hz 3.22 New Material (Medium Small Size) 11Hz 2.8 New Material (Large Large Density) 13Hz 3.83 New Material (Large Medium Density) 12Hz 3.9 New Material (Large Small Density) 12Hz 4.5
Experiments have shown that, under our defined packaging conditions, the resonance frequency of the tested system with the polystyrene foam as the buffer, the resonant frequency of the large foam cushioning pad is 11Hz, the medium foam appears at 13Hz, and the small The foam pad has a resonance frequency of 12 Hz. The new material has a resonant frequency of about 11 to 14 Hz.
Although the resonant frequency values ​​of the two types of buffer package corner pads are relatively close, the transfer rate of the new type of cushioning material is far less than that of the foam, and it far exceeds the vibration absorption performance of the foam in terms of performance, and has played a good effect.
Third, the conclusion From the shock resistance, vibration absorption performance point of view, the new material can basically meet this requirement. It can be seen from the experimental data that the amount of sizing should be controlled to be both firm and deformable, and it is easy to absorb the impact energy and damping effect. Adjusting the density of the material within a certain range can improve the vibration absorption performance.
Generally speaking, the new buffer material can replace the polystyrene foam plastic buffer packaging, but should pay attention to the raw materials, influencing factors and combinations from the production process to achieve the elastic buffering effect of its deformation, and it has It should play the role of vibration absorption damping energy.
From our research data, it is difficult to find the minimum cushioning system in the traditional sense by using the test data of cushioned corner pads made from corrugated board corner materials. This will give a new topic for designing and using this material in the future. The design method of the minimum buffer coefficient adopts "analogous" design and experimental verification methods. We have reason to miss, with the emergence of new buffer materials, and when the theory is not sound, the "analogy" design and experimental verification methods are more reasonable methods.
The above conclusions are based on our experimental data processing. Due to the limitations of our standards, if there is something wrong, we urge you to criticize and correct me. (Author: Tianjin Institute of Light Industry microwave Liu Ding Nan Liu Zheng Gu Gong Li Rui Zhang Yuzhe)