Water-soluble polymers test methods

There have been numerous communications on the subject of biodegradation test methods, including aerobic compost (30), anaerobic bioreactor (31), general methodology and future directions (32—34), and a fine review article (24). ASTM (22) and MITI (35) have also set forth standard testing protocols for plastics, as shown in Table 2, whereas OECD test methods (29) are more suited to water-soluble polymers. 

TEST METHODS FOR BIODEGRADABLE WATER-SOLUBLE POLYMERS... 

Masuda (1994) have also set forth standard testing protocols for plastics as shown in Table 3, whereas OECD test methods(1981) are more suited for water-soluble polymers. 

Based on an inquiry made on behalf of the superabsorbent polymer manufacturers, performance testing items include appearance, smell, water uptake, water retention, rate of water absorption, particle size distribution, bulk density, pH, gel strength, durability, dry weights, residual monomer, and water soluble components. The testing items that should be standardized are water uptake and rate of water absorption [151]. Testing method preferences include ... 

Waste-management requirements and disposal options are the drivers for research to develop environmentally biodegradable polymers and to establish laboratory testing protocols. It is commercial opportunities that indicate polymer types, structures, properties and uses that dictate waste management and disposal requirements. Disposal methods and locations identify the testing protocols that must be established for polymers in order to evaluate their environmental degradation under laboratory simulated environmental exposure conditions. Major options for the disposal and waste-management of water-soluble polymers are indicated in Fig.2. 

Test Methods for Biodegradable Water-Soluble Polymers... 

In the Phadebas TM amylase test (72) (Pharmacia Labs) the substrate was a water insoluble cross-TTnked blue starch in tablet form which also contains some inert ingredients, sodium and potassium phosphate buffer salts and sodium chloride. This polymer was hydrolyzed by amylase into water soluble blue starch fragments. After centrifugation the absorbance of the blue supernatant was proportional to the activity of amylase present in the test samples. The day to day variation on a quality control serum had a coefficient of variation of 2.7% based on 30 days of data in our laboratory. The method is simple, reproducible and uses microquantities of serum. 

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