Bottle weight controller

We measure the permeation rate of liquids through bottles by filling them with the liquid of interest and placing them in a controlled atmosphere chamber. At intervals we remove the bottles, weigh them and return them to the chamber. We repeat this procedure over a period of days, or even weeks, until their rate of weight loss reaches a steady value. We calculate the permeability factor from Eq. 8.10. 

Among the controlling factors in the production of bottles from PET are the molecular weight of the polymer and the draw ratio applied. The molecular weight required is in general higher than that of the polymer manufactured for... 

The dual treatment in the Buhler botde-to-bottle process is an important aspect in food safety considerations. The bulk of the contaminants are removed in the extruder. However, the SSP process provides a back-up to remove any residual contaminants, which are now homogeneously distributed in the PET pellets. The cleaning becomes a well-defined and predictable diffusion controlled process, which is defined by pellet diameter, treatment temperature and time. The same parameters also regulate the SSP process. For products with similar reactivity, a known increase in molecular weight during the solid-state process will also provide a known cleaning efficiency. 

NOTE Small temperature fluctuations can result in large errors in calculated densities. The temperature of all materials (bottle and solutions) should therefore be carefully controlled during all stages of the procedure using either a temperature-controlled chamber or a water bath. If a water bath is used, all excess water must be wiped off the specific gravity bottle prior to measurements to prevent evaporative cooling effects and errors in weight determination. 

The volumetric filler is also electronically controlled, ensuring an accurate dose of product to each container. For PET bottles, which creep under car-bonation pressure, there is the drawback that they will have differing fill levels over a filling cycle due to the fact that no two bottles are ever exactly identically blow-moulded. With light weighting, this problem is exacerbated. 

Control Preparations Transfer 50.0-g portions of unmodified (underivatized) waxy corn starch into five separate pressure bottles, and add 125 mL of 2 N sulfuric acid to each bottle. Add 0.0, 0.5, 1.0, 2.0, and 5.0 mL of the Standard Preparation to the bottles, respectively, giving propylene chlorohydrin concentrations, on the starch basis, of 0, 0.5, 1, 2, and 5 mg/kg, respectively. Calculate the exact concentration in each bottle from the weight of Propylene Chlorohydrins used in making the Standard Preparation. Clamp the tops in place, swirl until the contents of each bottle are completely dissolved, and proceed with the hydrolysis, neutralization, filtration, extraction, extract concentration, and final dilution as directed under Sample Preparation. 

Four types of fabric substrates were cyanoethylated the control, acid hydrolyzed, 50 and 100 Mrad. Fabric specimens 19 X 89 mm were sprayed with a fine mist of 2% NaOH solution using a hand spray bottle until a 100% pickup by weight was achieved. The specimens were then left to air dry until just damp. Six samples were then placed on a rack inside the sealed reaction vessel, which had inlet and outlet connections to permit the acrylonitrile vapor to flow through and around the reactive fabric. This vessel was connected to two bubble bottles containing water and acrylonitrile with which to saturate nitrogen gas as it entered the reaction vessel. The water was necessary to swell the cellulose so the acrylonitrile could penetrate. It was determined that varying nitrogen flow rates and reaction time had little effect on the percent add-on. 

The preliminary characterization analysis on the bulk material from river Ruhr revealed also the necessity of a fortification step. However, for these materials, it was decided to opt for a low concentration level (down to around 0.1 pgL-1 per compound) achieved by fortifying the bottled materials just before dispatch of the samples (two days maximum in advance). Due to the chosen spiking procedure, a check of the integrity of the sample received by the laboratories was considered necessary and achieved by a control of the weight of the bottle. Additionally, and once again because of the spiking procedure used, for these materials participants were requested to analyse samples immediately after receipt. 

In a second laboratory experiment, the chemical persistence of carbofuran applied as Furadan 10G (the commercial sand-coated granule) and 2 Sierra controlled-release carbofuran formulations (samples no. 32-47-2, 9.1% AI and 32-48-2, 9.7% AI) were monitored for two months in three soil types, no. 29, 46, and 44 (Table I). Three-hundred forty-one grams (300 g oven-dry weight) of each soil were weighed into glass bottles and fortified with 1.5 g of one of the three formulations. The actual rates of application were 455 ppm (no. 32-47-2), 485 ppm (no. 32-48-2), and 500 ppm (Furadan 10G). The soils were thoroughly mixed and adjusted to 25% of MHC. The bottles were sealed with Parafilm and incubated at 25°C. At biweekly intervals, 20-g replicates of each soil were removed for quantitative analysis of carbofuran. 

The trials should deliberately investigate the mode for variations and failure route (care must be taken that trial-induced variations in the product are not released for consumer retail unless extensively checked). For example, failure/variation in a vacuum filling line can be caused by loss of vacuum, the result of seal damage from abrasion with the bottle rims. In a piston/ cylinder operation, density variations in the product (requiring strict analytical control) are a principal source of fill weight variation. 

Upon emptying the containers, three additional specimens were cut, blotted on filter paper to remove surface solvent, weighed and dried at 60°C in an air circulating oven. The solvent loss of these specimens in (g. toluene/g. dry polymer) was defined as the dynamic toluene sorption for the tested container. Equilibrium toluene sorption was determined at RT and 50°C by immersion to constant weight of replicated cutouts from control bottles. 

---