KR20140048405A - Evaluation method of biodegradation - Google Patents

Abstract

The present invention relates to an evaluation method for biodegradation rates and, more specifically, to a standardized evaluation method for biodegradation rates, which evaluates the biodegradation rate of a biodegradable polymer quickly and accurately in a short time to ensure reproducibility while promoting the convenience of measurement and enabling the evaluation at low costs. [Reference numerals] (AA) Reduction rate (%); (BB) Reaction time (h)

Description

Evaluation method of biodegradation

 The present invention relates to a method for evaluating biodegradation, and more particularly, to a method for evaluating biodegradability capable of accurately predicting actual biodegradability in a short time by promoting biodegradation of a biodegradable polymer.

Recently, domestic and global environmental pollution is a serious social problem. While plastic materials have contributed to abundant daily life and industrial development, various waste plastics and plastics released in large quantities according to the use of plastics have become one of the main causes of environmental pollution. Environmental hormones generated by incineration or landfilling of waste vinyl or plastics, dioxin with high toxicity, and air pollution due to incomplete combustion of waste are causing serious environmental pollution.

On the other hand, as the environmental pollution problem caused by the above-mentioned waste plastics has become a big social problem, the pressure of commercialization and mandatory use of environmentally-friendly biodegradable plastic resins that are decomposed by microorganisms in the soil by landfilling after use of plastics has recently increased. It is getting stronger. In general, "biodegradable" means the ability of a compound to be finally decomposed into biological resources such as methane, carbon dioxide and water or inorganic salts by microorganisms and / or environmental factors. In order to protect the global environment, various international environmental conventions in various fields are being promoted and executed one after another. As the environmental awareness and the consumer's awareness of chemical products and various consumer products are changed, more environmentally friendly products are developed. Efforts to continue are ongoing. Already, developed countries such as Germany, Italy and the United States are making mandatory use of biodegradable resins for shopping bags and plastic bottles.

For the study and use of such biodegradable polymers, the method of measuring biodegradability and preparing biodegradability standards should be the first priority. However, despite studies of biodegradable polymers and the rapid increase in products made of biodegradable polymer compounds and market expansion, it was not easy to measure the biodegradability of the biodegradable polymer compounds quickly, quantitatively and reproducibly. Accordingly, various studies are being conducted to more effectively measure biodegradability.

Research on measuring biodegradability of biodegradable polymer materials has been actively conducted in the United States and Japan for settlement as a standardized method. In the United States, methods for measuring biodegradation in accordance with environmental conditions that will eventually reach the polymers that have been used and then discarded continue to be published in ASTM regulations. The landfill condition is the largest part of the environmental conditions that will eventually be reached by the discarded polymer material after use, and it is required to establish a method for measuring biodegradation under these conditions. There was a problem that it was difficult to evaluate biodegradability quantitatively and reproducibly because the environmental conditions were not constant according to the place, and the measurement time was very long.

In addition, the biodegradation process according to the existing KS M 3100-1 is a biodegradation measuring method that is performed for at least 45 to 180 days at a temperature of 58 ° C. and a humidity of 50%. There has been a problem in the research on the efficient biodegradable polymers required.

 The present invention has been made to solve the above problems, an object of the present invention is to provide a biodegradability evaluation method that can be evaluated to have a rapid, accurate and reproducible biodegradability of a biodegradable polymer material in a short time.

 In order to solve the above problems, the present invention,

In the biodegradability evaluation method of the biodegradable polymer, the biodegradable polymer is immersed in 96-102 ℃ solvent to accelerate the hydrolysis, and then provides a biodegradation evaluation method for evaluating the degree of biodegradation by measuring the rate of change of intrinsic viscosity (IV). .

According to a preferred embodiment of the present invention, the biodegradation evaluation method can be evaluated based on the time it takes to reach the biodegradation degree 90% defined by the following [Equation 1].

[Equation 1]

y = aln (x) + b

In Equation 1 above,

 y: time to reach 90% biodegradation (days)

x: intrinsic viscosity (IV) change rate (%) when the said hydrolysis acceleration | stimulation process was performed for 24 hours

,

이다.
a, b is

,

to be.

According to another preferred embodiment of the present invention, the method for evaluating biodegradation can be evaluated based on the time taken to reach 60% biodegradability defined by Equation 2 below.

&Quot; (2) "

y = cln (x) + d

In Equation 2 above,

 y: time to reach 60% biodegradability (days)

x: intrinsic viscosity (IV) change rate (%) when the said hydrolysis acceleration | stimulation process was performed for 24 hours

,

이다.
c, d

,

to be.

According to another preferred embodiment of the present invention, the hydrolysis accelerated treatment time may be 24 to 96 hours.

According to another preferred embodiment of the present invention, the solvent may be any one or more selected from the group consisting of water, distilled water, phosphate buffer solution and sodium acetate buffer solution.

According to another preferred embodiment of the present invention, the solvent may have a pH of 7.0 to 7.4.

According to another preferred embodiment of the present invention, the hydrolysis acceleration may be treated by including 1.5 to 2.0% by weight of a biodegradable polymer in the solvent.

According to another preferred embodiment of the present invention, the method for evaluating biodegradation is to accelerate the hydrolysis accelerated hydrolysis, and then dried at 65 to 90 ℃ for 6 to 24 hours to measure the intrinsic viscosity (IV) change rate can do.

According to another preferred embodiment of the present invention, the intrinsic viscosity (IV) change rate is the intrinsic viscosity (IV) of the biodegradable polymer before hydrolysis acceleration treatment and the intrinsic viscosity (IV) of the dry biodegradable polymer after hydrolysis acceleration treatment The rate of change can be measured.

According to another preferred embodiment of the present invention, the biodegradable polymer may be immersed in any one or more forms selected from the group consisting of chips, yarns, films and sheets.

 The biodegradability evaluation method of the present invention can provide a standardized biodegradability evaluation method by evaluating the biodegradability of the biodegradable polymer material in a short time, while making it easy to measure and evaluating at low cost. Can be.

1 is a graph showing the change in intrinsic viscosity (IV) measured after the hydrolysis acceleration treatment according to an embodiment of the present invention.
Figure 2 is a graph showing the rate of change of intrinsic viscosity (IV) measured after the hydrolysis accelerated treatment according to an embodiment of the present invention.
Figure 3 is a photograph showing a hydrolysis accelerated treatment procedure according to an embodiment of the present invention.

Hereinafter, the present invention will be described in more detail.

As described above, the conventional biodegradation evaluation method is difficult to evaluate biodegradability quantitatively reproducibly, and it is very expensive, and at least 45 to 180 days are required for a very long time. There was a problem with the limit.

Accordingly, in the present invention, in the method for evaluating biodegradability of biodegradable polymers, the biodegradable polymers are immersed in a solvent at a high temperature of 96 to 102 ° C. to accelerate hydrolysis, and then biodegradation is evaluated by measuring the intrinsic viscosity (IV) change rate. The solution to the above problem was sought by providing a drawing evaluation method. Through this, the biodegradability can be easily measured, and the biodegradability of the biodegradable polymer material can be evaluated quickly, accurately, and reproducibly in a short time, thereby providing a standardized biodegradation evaluation method.

Biodegradable polymer is low molecular weight by primary decomposition under the condition of high temperature and humidity, and finally refers to secondary decomposition into water, carbon dioxide, methane gas, etc. by biological action of microorganisms, More preferred biodegradable polymers may include aliphatic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, or these. Biodegradable polyesters and diols having 2 to 14 carbon atoms, ethylene glycol, propylene glycol and butylene glycol trimethyl glycol (Trimethyl Glycol), Tetraethylene Glycol, Pentamethyl Glycol, Hexamethylene Glycol, Heptamethylene Glycol, Octamethylene Glycol, Nonamethylene Glycol, Decamethylene Glycol, Undecamethylene Glycol, Dodecamethylene Glycol At least one selected from the group consisting of tridecamethylene glycol (Tridecamethylene Glycol), tetradecamethylene glycol (TetradecamethyleneGlycol), or a mixture consisting of two or more of these, a biodegradable polyester.

According to a preferred embodiment of the present invention, the hydrolyzable polymer is accelerated by immersing the biodegradable polymer in a high temperature solvent for a certain time, and the biodegradable polymer may be low molecular weight in a short time. Intrinsic viscosity (IV) change rate is measured to determine the degree of hydrolysis of the biodegradable polymer by hydrolysis accelerated treatment. Intrinsic viscosity (IV) is a measure of the molecular weight by measuring the viscosity of the polymer solution using a capillary tube, the decrease in intrinsic viscosity (IV) may be a measure of the molecular weight decrease. Therefore, the biodegradable polymer is hydrolyzed to accelerate the first decomposition within a short time, and the intrinsic viscosity (IV) change rate of the low molecular weight biodegradable polymer can be measured to accurately determine the degree of biodegradability within a short time.

Specifically, the biodegradable polymer used as a sample in the method for evaluating biodegradation is not particularly limited as long as it is in a solid or liquid form that can be weighed. More preferably, a single or mixed form of chips, yarns, films or sheets, etc. Can be immersed in

The biodegradable polymer is immersed in a 96 to 102 ℃ solvent to accelerate the hydrolysis. If the solvent for accelerated hydrolysis is less than 96 ℃, the rate of hydrolysis accelerates slowly, making it unsuitable for predicting biodegradation within a short time, which is the purpose of this evaluation method. There may be a problem in the evaluation of intrinsic viscosity (IV), causing excessive physical damage, which makes it impossible to maintain constant conditions during accelerated treatment time.

The solvent used for the hydrolysis accelerated treatment of the biodegradable polymer is not particularly limited as long as it is controlled to maintain a certain condition (PH, etc.) during the accelerated hydrolysis treatment time, more preferably distilled water, phosphate buffer solution (PH 7.4) And sodium acetate buffer solution (PH 7.0) or the like, or a mixture thereof.

The solvent may have a pH of 7.0 to 8.0, and maintain a constant PH during hydrolysis accelerated treatment. The proportion or degree of hydrolysis reaction is known to be most affected by the strength of the acid or base. Therefore, when the pH of the solvent is less than 7.0 or the pH is greater than 8.0 may affect the degree of hydrolysis reaction according to the difference in the strength of the acid or base may inhibit the evaluation of biodegradability and may reduce the reproducibility.

The hydrolysis acceleration treatment may be treated by including 1.5 to 2.0% by weight of a biodegradable polymer in the solvent. Less than 1.5% by weight or more than 2.0% by weight may affect the reaction rate depending on the reaction mole ratio of the reactant and the sample, there may be a problem that the reaction proceeds very fast or very slow.

By accelerated hydrolysis according to a preferred embodiment of the present invention it is possible to firstly decompose the biodegradable polymer in a short time to low molecular weight, through which the biodegradability of the biodegradable polymer can be evaluated in a short time. The hydrolysis accelerated treatment time may preferably be 24 to 96 hours. If it is less than 24 hours, it is impossible to compare biodegradation due to insufficient hydrolysis reaction, and if it exceeds 96 hours, it takes a long time to inhibit efficient biodegradation evaluation, and the decomposition progresses rapidly or reaches the decomposition saturation point. In this case, the rate of hydrolysis is so fast that the decomposition saturation point has already been exceeded, which can lead to errors in predicting biodegradability.

After the biodegradable polymer is subjected to a hydrolysis accelerated treatment for a predetermined time period and dried at 65 to 90 ° C. for 6 to 24 hours, the intrinsic viscosity (IV) change rate can be measured. If the temperature is out of the above range in the drying step after the hydrolysis treatment, the polymer may decompose due to the high temperature, so that the intrinsic viscosity (IV) may be lowered.

The rate of change of intrinsic viscosity (IV) for evaluating the degree of biodegradability of biodegradable polymers is based on the intrinsic viscosity (IV) before hydrolysis accelerated treatment of biodegradable polymer and the inherent viscosity (IV) of dry biodegradable polymer after hydrolysis accelerated treatment. It can be measured by The biodegradable polymer having a higher intrinsic viscosity (IV) reduction rate compared to the initial value of the dry biodegradable polymer after the hydrolysis acceleration treatment was calculated, and thus the biodegradability was higher.

For example, referring to FIG. 1, polyethylene adipate terephthalate (PEAT) modified with PLA (Polylactic acid), which is a representative biomass material having excellent biodegradability, and adipic acid in 10 mol%, according to a preferred embodiment of the present invention After the accelerated decomposition treatment, it was dried to show the intrinsic viscosity (IV) change rate value. As the content of PEAT, which has relatively low biodegradability, the intrinsic viscosity (IV) decrease rate is smaller, and the higher the PLA content, which has better biodegradability, the higher the intrinsic viscosity (IV) decrease rate value is.

In addition, regular PET with little biodegradability, aliphatic acid-modified polyester and PLA in accordance with a preferred embodiment of the present invention, after hydrolysis accelerated treatment, and dried to look at Figure 2 showing the intrinsic viscosity (IV) change rate value, biodegradation PLA shows excellent decrease in intrinsic viscosity (IV), and PET shows small value. Polymer A and B, which are considered to have similar biodegradability due to the same modification rate of aliphatic acid, exhibit almost similar intrinsic viscosity (IV) reduction rate behavior, and Polymer A and B which are more biodegradable due to the modification of aliphatic acid are polymer A and B. The larger intrinsic viscosity (IV) decrease rate shows that the degree of biodegradability can be evaluated reproducibly.

Biodegradability evaluation method according to an embodiment of the present invention can be evaluated based on the time it takes to reach the biodegradation degree 90% defined by the following [Equation 1].

[Equation 1]

y = aln (x) + b

In Equation 1, x is the intrinsic viscosity (IV) reduction rate (%) of the biodegradable polymer compared to the initial value measured after drying and accelerating the hydrolysis treatment for 24 hours, y is the biodegradability of the target biodegradable polymer The number of days it takes to reach 90%. In Formula 1, the range of a may be -200.7 to -164.2, and the range of b may be 777.13 to 949.83. If a, b is out of the above range, there may be a problem that a significant biodegradability evaluation is difficult to be obtained because the error range of the time (days) for which the calculated biodegradation degree reaches 90% exceeds 10%.

In addition, the biodegradation evaluation method according to a preferred embodiment of the present invention can be evaluated based on the time it takes to reach 60% biodegradability defined by Equation 2 below.

&Quot; (2) "

y = cln (x) + d

In Equation 2, x is the intrinsic viscosity (IV) reduction rate (%) of the biodegradable polymer compared to the initial value measured after drying and accelerating the hydrolysis treatment for 24 hours, y is the biodegradability of the target biodegradable polymer The number of days it takes to reach 60%. In Equation 2, the range of c may be -133.9 to -109.5, and the range of d may be 522.55 to 638.67. If c and d are out of the above ranges, there may be a problem that a significant biodegradability evaluation is difficult to be obtained because the error range of the time (days) for calculating the biodegradability obtained to reach 60% exceeds 10%.

The biodegradability evaluation method of the present invention, after accelerating the hydrolysis acceleration of the biodegradable polymer, by measuring the rate of change of intrinsic viscosity (IV) compared to the initial value, it is relatively simple and reproducible within a short time, and the degree of biodegradability of the biodegradable polymer relatively Can be evaluated Furthermore, by substituting the rate of change of intrinsic viscosity (IV) measured as described above into Equations 1 and 2, the time taken for the biodegradability of the biodegradable polymer to reach 60% or 90% can be predicted quantitatively in a short time. It can be effectively used for biodegradation certification acquisition test.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples should not be construed as limiting the scope of the present invention, and should be construed to facilitate understanding of the present invention.

<Examples 1 to 7>

 The content ratio of polyethylene adipate terephthalate PEAT (PolymerA) in which 10 mol% of polylactic acid (PLA) and adipic acid was modified is 0: 100, 10:90, 30:70, 50:50, 70:30, and 90: The hydrolysis accelerated treatment was carried out in the following manner, differing from 10, 100: 0.

PLA / PEAT Chip was immersed in 1.8% by weight of distilled water (PH7.4) in the vial and hydrolyzed in 100 ℃ water bath. After 24 hours, 96 hours, the sample was taken out, washed lightly, and vacuum dried at 90 ° C. for 24 hours. After drying, the intrinsic viscosity (IV) of the chip was measured to calculate the degree of reduction after hydrolysis compared to the initial value, and the result is shown in FIG. 1.

Referring to FIG. 1, the higher the content of PEAT, which is relatively low in biodegradability, the smaller the intrinsic viscosity (IV) reduction rate is, and the higher the biodegradable PLA content, the higher the intrinsic viscosity (IV) reduction rate value is. You can check it.

<Examples 8 to 13>

Polymer A, a polyester (PEAT) modified 10% by weight of adipic acid with aliphatic acid, Polymer B, a polyester (PEGT) modified with 10% by weight of glutaric acid, using aliphatic acid Polymer C which is 20 mol% modified polyester (PEGT) with tartaric acid, and Polymer D which is polybutylene-adiphate-terephthalate (PBAT) modified with adipic acid with aliphatic acid , PLA and PET (Polyethyleneterephthalate) was carried out in the same manner as in Example 1 except that the intrinsic viscosity (IV) reduction rate was measured by applying an intrinsic viscosity measuring instrument (AVS 370) over time to accelerate the hydrolysis treatment. The results are shown in Table 1 and FIG.

Reaction time (h) 10 24 48 72 96 120 144 168 192 216 240 264 288 312 Example 8
(PolymerA) IV
(%) 5.9 7.4 26.5 35.3 45.6 54.4 60.3 66.2 69.1 70.6 73.5 77.9 77.9 79.4 Example 9
(PolymerB) IV
(%) 4.4 10.3 23.5 36.8 42.6 50.0 57.4 61.8 69.1 70.6 72.1 76.5 76.5 79.4 Example 10
(PolymerC) IV
(%) 18.8 39.1 54.7 65.6 79.7 79.7 81.3 81.3 82.8 84.4 82.8 84.4 Example 11
(PolymerD) IV
(%) 21.0 41.4 60.5 71.3 77.7 83.4 86.0 86.0 88.5 89.2 89.2 89.8 89.8 Example 12
(PLA) IV
(%) 74.0 88.8 90.5 91.1 90.5 91.7 91.7 91.7 92.3 92.9 92.9 92.9 Example 13
(PET) IV
(%) 0.0 1.6 7.9 11.1 15.9 19.0 23.8 27.0 31.7 33.3 33.3 39.7 41.3 44.4

PLA, which has high biodegradability, shows the largest reduction in intrinsic viscosity (IV), and PET shows a small value. Polymer A and B, which are considered to have similar biodegradability due to the same modification rate of aliphatic acid, exhibit almost similar intrinsic viscosity (IV) reduction rate behavior, and Polymer A and B which are more biodegradable due to the modification of aliphatic acid are polymer A and B. The intrinsic viscosity (IV) decreased more. Up to 312 hours were used to determine the decomposition saturation point and biodegradation.However, even for short-term hydrolysis accelerated treatment within 312 hours, the degree of biodegradability can be accurately and reproducibly evaluated according to the intrinsic viscosity (IV) reduction rate value. .

&Lt; Comparative Examples 1 to 4 >

Polymer A, B, C and PLA was carried out in the same manner as in Example 8 except that the hydrolyzed in 50 ℃ distilled water. The results are shown in Table 2.

<Comparative Examples 5 to 8>

Polymer A, B, C and PLA were added to the solvent adjusted to pH 7.4 using phosphate buffer, CaCl ₃ 0.1M, enzyme Lipase (from pseudomonas cepacia), and the enzyme temperature was adjusted to 50 ° C. Was carried out in the same manner as in Example 8. The results are shown in Table 2.

division Reaction time (h) Kinds Temperature (℃) 48 96 168 216 Example 8 Polymer A / Distilled Water 100 26.5 45.6 66.2 70.6 Example 9 Polymer B / Distilled Water 100 23.5 21.9 23.0 70.6 Example 10 Polymer C / Distilled Water 100 54.7 79.7 81.3 84.4 Example 12 PLA / distilled water 100 90.5 90.5 91.7 92.9 Comparative Example 1 Polymer A / Distilled Water 50 0.0 0.0 0.0 0.0 Comparative Example 2 Polymer B / Distilled Water 50 1.0 1.5 2.9 2.9 Comparative Example 3 Polymer C / Distilled Water 50 0.8 2.3 3.6 4.7 Compare to 4 PLA / distilled water 50 23.2 25.7 27.6 28.7 Comparative Example 5 Polymer A / Enzyme 50 0.0 1.5 1.5 2.9 Comparative Example 6 Polymer B / Enzyme 50 1.5 2.9 4.4 2.9 Comparative Example 7 Polymer C / Enzyme 50 1.6 3.1 7.8 12.5 Comparative Example 8 PLA / enzyme 50 22.5 25.4 32.0 42.0

The intrinsic viscosity (IV) reduction rate value of Comparative Examples 1 to 4 using distilled water at 50 ° C. beyond the hydrolysis accelerated treatment temperature range of the biodegradability evaluation method of the present invention is used to evaluate the degree of biodegradability of the biodegradable polymer. Too small was not desirable. Compared to Examples 8 to 10 and 12 belonging to the hydrolysis accelerated treatment temperature range of the present invention, Comparative Examples 1 to 4 are difficult to evaluate the biodegradability itself, and the accuracy is also poor, and for a long time of more than 624 hours at a temperature of 50 ℃ The hydrolysis may be able to evaluate the biodegradability, but this may be inefficient and reproducible due to the problem of changing the pH of the solvent, the reaction molar ratio of the solvent and the sample as it takes a long time.

<Experimental Example>

Biodegradability results evaluated by the amount of CO ₂ generated according to the KS M 3100-1 standard and the decomposition behavior obtained through the equations 1 and 2 using the results according to Examples 8 to 12 are shown in Table 3 .

Equation 1 uses y = -182.5ln (x) + 863.48, and Equation 2 uses y = -121.7ln (x) + 580.61 to derive the number of days it takes to reach 90% and 60% biodegradability. It was.

x 90%
Days of arrival (y) 60%
Days of arrival (y) Biodegradation according to the amount of CO ₂ generated 90%
Days reached 60%
Days reached Example 8 7.4 498 337 520 345 Example 9 10.3 438 297 420 290 Example 10 39.1 194 134 180 130 Example 11 41.1 184 127 180 125 Example 12 88.8 45 35 50 40

As can be seen in Table 3, the biodegradability 60% and 90% reached days derived through Equation 1, 2 according to the preferred embodiment of the present invention showed an accuracy within 10% of the error range. While the conventional biodegradation evaluation takes a long time of at least 45 days to 180 days, according to the biodegradation evaluation method of the present invention, the biodegradability evaluation method is rapidly performed within 1 to 4 days. Accurate and reproducible results can be obtained.

Claims (10)

In the biodegradability evaluation method of the biodegradable polymer,
A biodegradation evaluation method of evaluating the degree of biodegradation by measuring the rate of change of intrinsic viscosity (IV) after immersing the biodegradable polymer in a solvent at 96 to 102 ° C. The method of claim 1,
The biodegradation evaluation method is a biodegradation evaluation method characterized in that the evaluation based on the time it takes to reach the biodegradation degree 90% defined by the following [Equation 1].
[Equation 1]
y = aln (x) + b
In Equation 1 above,
y: time to reach 90% biodegradation (days)
x: intrinsic viscosity (IV) change rate (%) when the said hydrolysis acceleration | stimulation process was performed for 24 hours
a, b is

,

to be. The method of claim 1,
The biodegradation evaluation method is a biodegradation evaluation method characterized in that the evaluation based on the time it takes to reach 60% biodegradation degree defined by the formula (2).
&Quot; (2) &quot;
y = cln (x) + d
In Equation 2 above,
y: time to reach 60% biodegradability (days)
x: intrinsic viscosity (IV) change rate (%) when the said hydrolysis acceleration | stimulation process was performed for 24 hours
c, d

,

to be. The method of claim 1,
The hydrolysis accelerated treatment time is a biodegradation evaluation method, characterized in that 24 to 96 hours. The method of claim 1,
The high temperature solvent is water, distilled water, phosphate buffer solution and sodium acetate buffer solution, characterized in that any one or more selected from the group consisting of. The method of claim 1,
The solvent has a pH of 7.0 to 8.0 characterized in that the biodegradability evaluation method. The method of claim 1,
Accelerating the hydrolysis is biodegradability evaluation method characterized in that the treatment containing 1.5 to 2.0% by weight of a biodegradable polymer in the solvent. The method of claim 1,
The method for evaluating biodegradability is to evaluate the rate of change of intrinsic viscosity (IV) by drying the biodegradable polymer after hydrolysis accelerated treatment for 6 to 24 hours at 65 to 90 ℃. The method of claim 1,
The intrinsic viscosity (IV) change rate is a biodegradation evaluation characterized by measuring the change rate between the intrinsic viscosity (IV) of the biodegradable polymer before hydrolysis acceleration treatment and the inherent viscosity (IV) of the dry biodegradable polymer after hydrolysis acceleration treatment Way. The method of claim 1,
The biodegradable polymer is biodegradable evaluation method characterized in that the immersion in any one or more forms selected from the group consisting of chips (Chip), yarn, film and sheet.

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