GB/T 12010.5-2010Plastic -- Poly (vinyl alcohol) (PVAL) materials -- Part 5: Determination for average polymerization degree (English PDF)

Foreword

GB/T 12010 "plastic material polyvinyl alcohol (PVAL)" is divided into eight sections.

--- Part 1. Designation system and basis;

--- Part 2. Performance measurement;

--- Part 3. Specifications;

Part --- Chapter 4. pH value measurement;

--- Part 5. Determination of the average degree of polymerization;

--- Part 6. Determination of particle size;

--- Part 7. Determination of sodium hydroxide;

--- Part 8. Determination of transparency.

This section GB/T Part of 512,010, and JISK6726:1994 (2003 Confirmafion) "polyvinyl alcohol test method" (Japanese Version) The non-equivalent.

This Part replaces GB/T 12010.9-1989 "Determination of average polymerization degree of polyvinyl alcohol." this section compared with the GB/T 12010.9-1989 The main changes are as follows.

--- Increasing the reference document (Chapter 2 of this edition);

--- The 30 °C when water flows in the Ostwald viscometer adjusted by the time (100 ± 10) s to (100 ± 20) s (1989 version 4.12, this Version 5.1);

--- Increased the degree of hydrolysis of 97% (mole fraction) above PVA material pretreatment (edition 6.1);

--- High alkali, low alkali alcoholysis polyvinyl specimen sample weight for a unified (1989 Version 5, this version 6.2).

This part is proposed by the China Petroleum and Chemical Industry Association.

This part of the National Standardization Technical Committee of plastic products and plastic resins General Methods Chapter (SAC/TC15/SC4) centralized.

This section is responsible for drafting unit. Hunan Xiangwei Limited.

This section participated in the drafting unit. China Petrochemical Group of Sichuan Vinylon Works, Ltd. Yunnan Yun-dimensional, synthetic resin national quality supervision Governor Inspection Center.

1 Scope

This section GB/T 12010 specifies the Ostwald viscometer with an aqueous solution of polyvinyl alcohol material viscosity properties were measured by the intrinsic viscosity calculation the method of average degree of polymerization of the polyvinyl alcohol material.

This section applies to the determination of the average degree of polymerization of the alcohol solution is greater than 70% (mole fraction) of the polyvinyl alcohol material.

2 Normative references

The following documents contain provisions which, through reference GB/T 12010 in this section constitute provisions of this section. For dated reference documents Member, all subsequent amendments (not including errata content) or revisions do not apply to this section, however, encouraged to reach under this section Parties to research agreement to use the latest versions of these documents. For undated reference documents, the latest versions apply to this section.

GB/T 603 chemical reagent in test methods - Preparations with Laboratory use specifications and test methods GB/T 6682 Analysis Principle 3 Determination of intrinsic viscosity aqueous solution of polyvinyl alcohol, polyvinyl alcohol calculates an average degree of polymerization of the material.

4 Reagents

When this part of the reagents and water, unless otherwise specified, refer to analytically pure reagents and GB/T 6682 in the third grade water.

As used in this part of the preparations and products, except where noted according to GB/T 603 formulation.

4.1 methanol.

4.2 Sodium hydroxide solution. c (NaOH) = 12.5mol/L.

Weigh 500g of sodium hydroxide, dissolved in water and diluted to 1000mL.

4.3 Phenolphthalein. 10g/L ethanol solution.

5 Instruments

5.1 Ostwald viscometer. Specifications Figure 1, made of hard glass.

Note. 30 °C, the water from A to B tick tick flowing time should be within (100 ± 20) s of.

5.2 glass frit funnel. No. P100 sintered glass.

5.3 Buchner funnel. diameter 100mm.

5.4 suction flask. 1L.

5.5 Oven. to maintain (105 ± 2) °C.

5.6 Stopwatch. accurate to 0.1s.

5.7 constant temperature water bath. (30.0 ± 0.1) °C.

5.8 Pipette. 10mL.

5.9 dryer. silica gel desiccant.

5.10 beaker. 500mL.