Degradation ASTM standard

ASTM Standards on Environmentally Degradable Plastics, ASTM Pubhcation Code Number (PCN) 03-420093-19, American Society for Testing and Materials, Philadelphia, Pa., 1993. 

For a particular set of conditions, acquire and store the spectrum of a sample similar to those involved in the application, either an ASTM standard or a stable material of reliable purity. The peak height or area of a particular Raman feature will serve as an indication of quantitative reproducibility and sensitivity. Be sure to record all relevant instrumental parameters, such as laser power, slit width, grating position, laser focusing parameters, integration time, CCD gain, and the like. The intent is to be able to reproduce these conditions at a future date, to check for response degradation. 

Support span-to-depth ratio, 236 Surface burning characteristics, ASTM standard, 480 Surface defects, 660 Surface roughness, 617 Surface rupture, 644 Surface tearing, 656, 667 Surface temperature of boards, 358 Surface temperature, 550 Susceptibility to microbial degradation, 414 Swagging extrudate, 660 Swell, 26, 209, 643... 

Polyamides and polyesteramides are more recent arrivals to the commercial biodegradable polymer field. Copolymers of either glycine or serine with e-aminocaproic acid are biodegradable. For example, biodegradable polyaspartic acid was synthesized (95% yield) at low cost [Koskan, 1992]. A copolymer of butylene-adipate and e-caprolactam was recently introduced by Bayer as BAK 1095. The material has T = 125°C, density of 1070 kg/m, tensile modulus of 180 MPa, maximum strain at break of 400%, tensile stress at break of 25 MPa, and it fully degrades in 300 days under the ASTM standard conditions. 

ASTM standards on environmentally degradable plastics , ASTM publication code number (DCN) 03-420093-19 (1993). 

Testing for degradation in aerobic landfill environments is typified by an ASTM standard method for soil burial (27), by changing the environment, where measurements of carbon dioxide are related to rate and degree of biodegradation. 

The extent of protective paint loss can be determined using standard methods for evaluating the degree of rusting on steel surfaces (see ASTM D 610 and Ref 5) and paint coating degradation (ASTM D 660 , D 662 , D 714", and D 772 ). 

More recently, international and national standards bodies, i.e. International Organization for Standardization (ISO), American Society for Testing and Materials (ASTM), Japanese Standards Association (JIS) and European Organization for Standardization (EN), have developed definitions related to the degradation of plastics. Nowad s, ISO and ASTM standards exist describing in detail the pmposes of biodegradable and compostable . 

The degradation of polylactic acid-based films by microorganisms extracted from compost was studied in a liquid medium [35], The application of the ASTM standard (ASTM D 5209-92) did not produce biodegradation of pieces of PLA film. With the ISO/CEN standard method (ISO/CEN 14852-1998), the percentage biodegradation after 45 days was found to be 30%. The different temperature profile of medium used in two standards seemed to be the major factor in explaining the observed differences. 

The results are listed in Table D.l, and shown graphically in Figure D.4. The results show that PHA film, PLA film, and the cellulose positive control degraded at least 90% in 180 days and met the degradation performance requirement in the ASTM standard. ASTM... 

An alternative is to use a biopolymer. In a similar film application for example, an option would be to use one that is starch-based and derived from corn (PCL, PVA or PLA). These biodegradable films, dependent on thickness, would meet the ASTM standard (American Standard for Testing Materials) and European [EN13432] for composting. However these materials require a controlled microbial environment such as an industrial compost facility before they will degrade. 

Steps topwards resolving this issue of oxidation followed by biodegradation are underway with the recently developed ASTM Standard Guidline, D 6954-04, which clearly indicates how to test polymers that degrade with oxidation preceeding biodegradation in all environments. The next steps are to extend the... 

The tendency of the color to become darker with time is often indicative of chemical degradation. The test is conducted with the aid of a colorimeter (NF T 60-104 and ASTM D 1500) and by comparison with colored glass standards. The scale varies from 0.5 to 8. The French specifications stipulate that diesel fuel color should be less than 5, which corresponds to an orange-brown tint. Generally, commercial products are light yellow with indices from 1 to 2. 

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