GB/T 24797.1-2009Film for wrapping rubber bales -- Part 1: Butadiene rubber (BR) and styrene-butadiene rubber (SBR) (English PDF)

Foreword

GB/T 24797 "rubber packaging film" is divided into three parts.

--- Part 1. Butadiene rubber (BR) and styrene - butadiene rubber (SBR);

--- Part 2. natural rubber;

--- Part 3. an ethylene - propylene - diene rubber (EPDM), acrylonitrile - butadiene rubber (NBR), hydrogenated acrylonitrile - butadiene rubber Rubber (HNBR), a vinyl acrylic rubber (AEM), acrylate rubber (ACM).

This section GB/T Part of 124,797.

This section is equivalent international standards ISO 20299-1:2006 "Rubber packaging films - Part 1. Butadiene rubber (BR) and styrene -Butadiene rubber (SBR) "(in English).

For ease of use, this section made the following changes.

--- Delete foreword international standards;

--- This section Normative references to our current national standards, the technical content of the corresponding international standards;

--- According to the Chinese language and customs, the standard text in the editorial changes.

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

This part of the National Standardization Technical Committee rubber and rubber products, synthetic rubber division Technical Committee (SAC/TC35 /SC6).

This section drafted by. China National Petroleum Chemical Research Institute Co., Ltd. Lanzhou Chemical Research Center.

Introduction

Most common synthetic rubber is made of a rubber compound after drying, briquetting made compact rubber temperature is still around after 60 °C, rubber Block coverage in automated packaging films and packaging procedures.

Packaging film should have sufficient strength to withstand the forces generated by the packaging process. During storage, the rubber will be cold, packaging the film should be able to withstand the pressures generated by the damage will result if the film and the rubber outer adhesions.

The purpose of the packaging film between the bag and the rubber bag at all times in a separated state, so that can be easily from the package Remove installed use. Since the packaging film strip both difficult and uneconomical from a rubber on each package, so the rubber mixing process in this package the film should be able to disperse in rubber, which requires less than the melting point of the packaging film must be reached during the mixing temperature is usually 120 °C ~ 160 °C.

Not yet a suitable method for the direct measurement dispersion.

If the mill mixing or kneading cycle process can not achieve the desired dispersion temperature, should be considered stripped from the rubber bag or film to use a lower melting point of packaging films.

GB/T 24797.1-2009/ISO 20299-1:2006 Rubber packaging film Part 1.

Butadiene rubber (BR) and styrene -Butadiene rubber (SBR) Warning --- the use of this standard should be familiar with general laboratory operations. This standard does not use security issues that may arise Make any statements. Responsibility of the user to establish appropriate safety and health mechanisms and to ensure that countries with formal laboratory conditions.

1 Scope

This section provides the physical characteristics of packaging materials and synthetic rubber used for general non-peel-off film. The film is to ensure oak Gum during storage, can be separated from each rubber package alone does not stick to each other.

This section applies to a styrene - butadiene rubber (SBR) and butadiene rubber (BR).

Some applications or processing methods require removal of the film, not the film for this section can be exfoliated.

2 Normative references

The following documents contain provisions which, through reference GB/T 24797 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 1633-2000 thermoplastics Vicat softening temperature (VST) Determination (idtISO 306.1994) GB/T 19466.3-2004 plastic differential scanning calorimetry (DSC) - Part 3. melting and crystallization temperature and enthalpy determination (ISO 11357-3:1999, IDT) GB/T 20220-2006 plastic film and sheeting average sample thickness, volume average mass per unit area and thickness measurement Weighing France (weighing thickness) (ISO 4591:1992, IDT)

3 Materials

Packaging film should be prepared by one of the following materials.

--- Low-density polyethylene (of LDPE);

--- Low-density polyethylene and an ethylene - vinyl acetate polymer (EVAC,) blend;

--- Suitable specifications EVAC.

Note. The film may be present in an antioxidant, a slip agent and a release agent.

4 Physical characteristics