Abstract: There is a risk that small molecules contained in bags will migrate into the contents of the package. This article takes the process of detecting evaporative residue content in vinegar packaging bags as an example to introduce a test method and testing equipment for testing the content of non-volatile small molecular substances in soft plastic packaging, and the ERT-01 evaporation residue for the testing equipment used. The equipment parameters and application scope of the Heng-Yi instrument are introduced to provide reference for the enterprises to carry out the detection of evaporation residue. Key words: vinegar, packaging bags, flexible plastic packaging, evaporation residue, non-volatile small molecular substances, evaporation residue constant weight meter, migration 1 , the meaning In the production process of flexible plastic packaging, in order to improve the packaging performance, additives such as antioxidants, lubricants, antistatic agents, and plasticizers are often introduced into the packaging. In addition, the resin raw materials used in the production of packaging are printed. The ink used, the adhesive used in the composite film, etc. are easy to introduce some small molecular substances into the soft plastic packaging. During the long-term contact between the flexible plastic packaging and the contents of the package, these small molecular substances tend to migrate slowly into the contents, contaminating the contents, especially under acidic conditions, high oil content and other environmental conditions. It will speed up and pose a serious threat to the health of consumers or users. Therefore, strengthening the monitoring of the migration of small molecules in soft plastic packaging is an effective measure to improve product safety and non-toxicity. 2 , the status quo At present, the export of small molecules in soft plastic packaging in China is mainly characterized by indicators of evaporation residue. The basic test procedure for the evaporation residue test is to replace the contents of the package with a soaking solution to simulate the migration of small molecules in a soft plastic package, and then analyze the weight of the material that migrated into the soaking solution. The detection of sample evaporation residue in this article refers to the reference test standard GB/T 5009.60-2003 “Analysis Method for Sanitary Standards of Polyethylene, Polystyrene, and Polypropylene Molded Products for Food Packaging†. 3 , test sample The vinegar packaging includes plastic bottles, glass bottles, and soft plastic bags. In this paper, a certain brand of vinegar packaging black and white film bag for the detection of samples, and according to the acidic characteristics of vinegar, select 4% of acetic acid as the test soaking solution. Figure 1 Common vinegar packaging 4 , test equipment This article uses the ERT-01 Evaporative Residue Constant Weight Instrument , developed and produced by Jinan Languang Electromechanical Technology Co., Ltd. , to test the evaporation residue of the sample. Figure 2 ERT-01 Evaporation Residue Constant Mass Meter 4.1 Test principle After soaking the sample with the soaking solution, the soaking solution is evaporated to dryness in a water bath and then placed in an evaporation residue meter. The soaking solution of the unsoaked sample is treated as a blank test in the same manner as the sample solution. The difference in mass after evaporation of the constant weight with the blank liquid is the evaporation residue of the sample. 4.2 Scope of application (1) This equipment is suitable for the testing of evaporation residue of various food packaging equipment and containers, such as packaging made of polyethylene, polypropylene, polystyrene, polyethylene terephthalate, nylon, etc. Containers, soft plastic packaging bags, natural rubber as the main raw material for bottled and canned food seal gaskets, gaskets, etc., vinyl chloride resin as the main raw material of the inner wall coating, etc., food cans inner wall epoxy phenolic coatings, plants Fibre pulp is a raw food container. (2) This equipment is suitable for the evaporation residue test of reagents that can evaporate and remove the main chemical reagents at boiling water bath temperature. (3) This equipment can meet many national standards, such as GB/T 5009.60 , GB/T 5009.64 , GB/T 5009.68 , GB/T 5009.69 , GB/T 5009.203 , GB/T 9740 and so on. 4.3 Equipment Parameters 5 , the test process (1) Measure the surface area of ​​the vinegar black and white bag sample to be tested. Then place the sample in a glassware. Add the corresponding volume of 4% acetic acid to the glassware according to the surface area of ​​the sample. Seal the glassware and place it at 60 °C . In the water bath, the sample was soaked at this temperature for 2 h . (2) Put the evaporating dish into the corresponding numbered tray in the test chamber of the evaporation residue constant weight apparatus according to the number, and measure the weight of the empty evaporating dish. (3) Take 200 mL of 4% acetic acid blank solution in a weighed fixed number of evaporating dish, remove 200 mL of soaking solution and place it into the weighed number of other evaporating dishes. Dry on a 100±5 °C water bath. (4) Put the evaporated evaporation pan into the corresponding numbered tray in the test chamber of evaporation residue constant weight instrument, and set the weighing interval time, drying temperature, weight difference, and reference cup ( ie, the evaporating dish containing blank liquid ) No. , test cup number and other parameter information, start the test, the equipment according to the set parameters for constant weight. (5) When the weight difference between the last two weighings of the evaporating dish is lower than the set value, the test is stopped and the equipment automatically calculates and displays the test result. 6 , test results The average evaporative residue of the black-and-white film bags for vinegar packaging used in this test was 5.69 mg/L . 7. Conclusion Evaporation residue is a physical index that characterizes the content of small molecules that can be eluted in the tested packaging samples. It is an important performance indicator that reflects the safe use of packaging equipment. ERT-01 Evaporation Residue Constant Weight Meter is a professional testing equipment for evaporation residue testing. The equipment overcomes the cumbersome process of artificial constant weight. The testing process is highly automated, avoiding the influence of human factors on the test results. More accurate and reproducible, 8 samples can be tested in a single test and can be weighed directly without drying and cooling. Labthink has always been committed to providing professional, advanced and high-end packaging testing equipment and testing services to customers around the world. The testing equipment and services provided include pharmaceutical packaging, food packaging, cosmetic packaging, printing, adhesives, automobiles, petrochemical, biotechnology, construction and new energy industries, understand the relevant testing equipment, you can visit Labthink website to view specific information or call the consultation. The more you understand, the more trust! Jinan Languang Electromechanical Technology Co., Ltd. is willing to take this opportunity to increase technical exchanges and cooperation with enterprises and institutions in the industry. Stick Bag Packing Machine Shanghai Boevan Packaging Machinery Co.,ltd , https://www.boevanpacking.com
