CN106147176B - A kind of halogen-free flameproof biomass board - Google Patents

Abstract

A kind of halogen-free flameproof biomass board, by PLA, plasticized starch, SBS, string, hydroxyl-terminated polylactic acid, nanometer sodium-based montmorillonite, 9, the oxide of 10 dihydro, 9 oxa-, 10 phospho hetero phenanthrene 10, melamine cyanurate, antioxidant, UV resistant agent composition, melting extrusion is into plate after the sheet material is blended by composition.Sheet material has good mechanical strength and toughness and an excellent combustion-supporting property, and materials environmental protection, processing are simple, available for high-grade ornamental flame-proof sheet material.

Description

A kind of halogen-free flame-retardant biomass board

technical field

The invention relates to a preparation method of a biomass board, in particular to a preparation method of a biomass board with excellent strength, toughness and excellent flame retardancy.

Background technique

Although plastic materials have excellent performance and wide applicability, they are derived from petroleum products and cannot be degraded. In today's resource crisis and environmental pollution are becoming more and more serious, looking for excellent performance and renewable alternative materials has become the current research field in the field of materials. top priority. Today's boards are used in a huge amount, and they are still basically plastic boards. It will be of great value to develop degradable boards with similar properties to plastics.

Among the current degradable materials, biomass comes from nature and can be fully degraded, so it is the most promising degradable material. At present, the main categories of biomass materials are starch and polylactic acid. Starch has been deeply studied because of its cheap price and wide range of sources, and has been modified and compounded to prepare a variety of daily and industrial products, such as starch-based films, starch tableware, etc. . However, starch has its natural defects. Its mechanical properties are poor and its performance is unstable, so it can only be used in fields that require low mechanical properties. The emergence of polylactic acid has changed this situation. Polylactic acid (PLA) is an aliphatic polyester with lactic acid (2-hydroxypropionic acid) as its basic structural unit. PLA can be produced by fermenting natural raw materials such as corn, or by polycondensation of lactic acid. PLA and its end products can be naturally decomposed into CO2 and water under composting conditions, which reduces solid waste emissions and is a green and environmentally friendly biological source material. PLA has mechanical properties similar to polystyrene, good flexural modulus and tensile strength, and can be used as the main material for the preparation of plates, but its thermal stability and impact resistance are poor, and there is a melt in the thermoforming process. The defect of low viscosity limits its application. After improving these shortcomings, PLA will be expected to be used as the best substitute of plastic materials in industrial and civil fields. In the research on the toughening modification of polylactic acid, polylactic acid is compounded with various materials to achieve the toughening effect, such as starch, polycaprolactone, polyethylene, etc., the above toughening methods have been widely studied, but due to the The strength itself is low, and there is a big difference in compatibility with polylactic acid, so the toughening effect is limited, and it seriously affects the strength of polylactic acid composites. In addition, there are many ways to toughen polylactic acid. A kind of toughened polylactic acid resin and its preparation method announced by CN101333333, the resin is composed of polylactic acid base resin, toughening agent styrene-butyl acrylate-acrylic acid copolymer, antioxidant B215; CN101935390A announced a After the terminal hydroxyl group of polybutylene succinate initiates the ring-opening polymerization of lactide, the polylactic acid toughening modifier is obtained through purification, and then added to polylactic acid for toughening and modification of the composite material. Preparation. But in general, the mechanical properties of polylactic acid-based materials, especially PLA-based biomass sheets, have not been completely resolved.

In addition, for the use of boards, flame retardancy is also a part that must be considered. For environmentally friendly biomass, only by adopting an environmentally friendly flame retardant method can the environmental protection characteristics of the material itself be maintained. At present, the biomass-based sheets are mainly polylactic acid materials, and the research on flame-retardant polylactic acid has received more attention. In addition to non-environmentally friendly halogen flame retardants, a variety of halogen-free, inorganic, and nano-flame retardants have been used in PLA. The new flame retardants reported in recent years include phosphorus-based phosphate esters, phosphorus compounds, etc., nitrogen-based melamine and its salts, etc., but the effect of using them alone is poor, and synergistic flame retardants such as phosphorus-nitrogen synergy can be achieved. better effect. Nano-flame retardants such as montmorillonite have a blocking effect, and their nano-scale can reduce the density of composite materials and improve mechanical strength, but they are easy to agglomerate when the amount is large; intumescent flame retardants are a good flame-retardant system, which contains There are three parts: acid source (such as ammonium phosphate, phosphate ester, etc.), carbon source (such as pentaerythritol and other carbon-rich polyols), and gas source (amine or amide compound). Different system innovations can lead to an efficient and environmentally friendly intumescent flame retardant system that is more suitable for PLA. For example, nano fillers are added to the traditional APP/MA flame retardant system for synergistic flame retardancy, petroleum-based char-forming agents are replaced with green-sourced starch, and part of the acid source is bio-based materials. In addition, new nanomaterials such as POSS and carbon nanotubes are also used for PLA flame retardancy. But on the whole, it is still difficult to find a balance between flame retardant performance, mechanical properties and environmental protection in the current flame retardant polylactic acid technology, especially in the domestic field of polylactic acid materials with excellent performance is still blank. It is imminent to develop new PLA materials with excellent mechanical properties and flame retardancy and to prepare biomass sheets with excellent properties.

Contents of the invention

The purpose of the present invention is to provide a biomass board with excellent mechanical properties and flame retardancy for the defects of poor mechanical properties and flame retardancy of the biomass board.

The purpose of the present invention is achieved through the following technical solutions:

A halogen-free flame-retardant biomass board, made of polylactic acid, plasticized starch, SBS, plant fiber, hydroxyl-terminated polylactic acid, nano-sodium montmorillonite, 9,10-dihydro-9-oxa-10-phosphorus Miscellaneous phenanthrene-10-oxide, melamine cyanurate, antioxidant, anti-ultraviolet agent

composition. Wherein, the mass parts of each component are:

Polylactic acid: 100 parts

Plasticized starch: 20-40 parts

SBS: 10-20 servings

Plant fiber: 5-10 parts

Hydroxyl-terminated polylactic acid: 5-10 parts

Nanonaki montmorillonite: 3-6 parts

9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide: 8-16 parts

Melamine cyanurate: 4-8 parts

Antioxidant: 2-4 parts

Anti-ultraviolet agent: 2-4 parts.

Further, the polylactic acid described in the present invention is poly L-lactic acid, poly D-lactic acid, or poly L, D-lactic acid composition, the molecular weight of the polylactic acid is optimally 300000-500000g/mol, again 150000-300000g /mol, again 80000-150000g/mol.

Further, the plasticized starch described in the present invention is cornstarch or tapioca starch plasticized by glycerol, and the quality of glycerin used for plasticization is between 20% and 35% of the starch.

Further, the plant fiber of the present invention is one of physically or chemically treated bamboo fiber, wood fiber, cotton fiber, bacterial fiber, its diameter is between 200nm-2μm, and the aspect ratio is between 20-500 between. The physical method can be mechanical crushing method, steam flash explosion method, and the chemical method can be acid activation method or alkali activation method.

Furthermore, the molecular weight of the hydroxyl-terminated polylactic acid described in the present invention is between 30,000-100,000 g/mol, and the proportion of hydroxyl groups in the terminal groups to the total terminal group molar ratio is between 70-90%.

Further, the nanometer sodium-based montmorillonite described in the present invention is lamellar particle, and its average chip thickness is less than 25nm, can adopt commercially available nanometer sodium-based montmorillonite, also can adopt calcium-based montmorillonite modification, modification can use NaCl Ethanol solution, sodium carbonate, sodium pyrophosphate, and sodium polyphosphate are used as modifiers to exchange calcium-based montmorillonite for sodium-based montmorillonite.

Further, the 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide of the present invention is an organophosphorous heterocyclic compound with high thermal stability, oxidation resistance and excellent For water resistance, commercially available products can be used.

Furthermore, the antioxidant of the present invention is one or more of antioxidant BHT, antioxidant 1010, antioxidant 1076, and antioxidant 164 mixed in any proportion.

Further, the anti-ultraviolet agent of the present invention is one or more of the ultraviolet absorbers UV-531, UVP-327, UV-9 and RMB mixed in any proportion.

Further, the processing technology of the halogen-free flame-retardant biomass plate of the present invention is:

(1) all raw materials are vacuum-dried at 50 degrees for 24 hours, and set aside;

(2) Blend all raw materials in a high-speed mixer at 60 degrees for 5-10 minutes, and the speed is 100-200rad/min;

(3) Put the blended raw materials into a screw extruder for melt extrusion, the melt extrusion temperature is 170-200 degrees, the screw speed is 150-250rad/min, and the residence time is 1-2 minutes.

Further, the beneficial effect of this invention is based on the interaction between all components, such as hydroxyl-terminated polylactic acid can interact with polylactic acid and starch, and hydroxyl-terminated polylactic acid can produce polycondensation during high-temperature extrusion to promote system compatibility Improvement of properties, SBS plays a toughening role in the system, plant fibers play a strengthening role, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, melamine cyanurate are used as chemical The gas source and acid source in the intumescent flame retardant, while the starch is not only used as the carbon source in the flame retardant, but also as a cost-reducing component in the sheet system. role.

detailed description

Exemplary implementation methods of the present invention will be described in detail below. However, these implementation methods are for exemplary purposes only, and

The present invention is not limited thereto.

Example 1

A halogen-free flame-retardant biomass board, made of polylactic acid, plasticized starch, SBS, plant fiber, hydroxyl-terminated polylactic acid, nano-sodium montmorillonite, 9,10-dihydro-9-oxa-10-phosphorus Miscellaneous phenanthrene-10-oxide, melamine cyanurate, antioxidant, anti-ultraviolet agent

composition. Wherein, the mass parts of each component is:

Polylactic acid: 100 parts

Plasticized starch: 32 parts

SBS: 15 copies

Vegetable fiber: 8 servings

Hydroxyl-terminated polylactic acid: 8 parts

Nanonaki montmorillonite: 5 parts

9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide: 12 parts

Melamine cyanurate: 6 parts

Antioxidant: 3 parts

Anti-ultraviolet agent: 3 parts.

The polylactic acid is poly-L-lactic acid, and the molecular weight of the polylactic acid is 300000-500000 g/mol.

The plasticized starch is tapioca starch plasticized by glycerin, and the quality of glycerin used for plasticization is 30% of the starch.

The plant fiber is physically treated bamboo fiber, its diameter is between 400nm-1um, and its aspect ratio is between 20-500. The physical method can be a mechanical crushing method combined with a steam flash explosion method.

The molecular weight of the hydroxyl-terminated polylactic acid is between 50000-80000 g/mol, and the proportion of hydroxyl groups in the terminal groups to the total terminal group molar ratio is 85%.

The average wafer thickness of the nanometer sodium-based montmorillonite is less than 25nm, and commercially available nanometer sodium-based montmorillonite is used.

The 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide is a commercially available product.

The antioxidant is antioxidant BHT.

The anti-ultraviolet agent is ultraviolet absorber UV-531.

The processing technology of the halogen-free flame-retardant biomass plate is:

1) All the raw materials were vacuum-dried at 50 degrees for 24 hours and set aside;

2) Blend all raw materials in a high-speed mixer for 6 minutes at 60 degrees, with a speed of 150 rad/min;

3) Put the blended raw materials into the screw extruder for melt extrusion, the melt extrusion temperature is 170-200 degrees, and the screw speed is

180rad/min, the residence time is 1.5 minutes.

Example 2

A halogen-free flame-retardant biomass board, made of polylactic acid, plasticized starch, SBS, plant fiber, hydroxyl-terminated polylactic acid, nano-sodium montmorillonite, 9,10-dihydro-9-oxa-10-phosphorus Miscellaneous phenanthrene-10-oxide, melamine cyanurate, antioxidant, anti-ultraviolet agent

composition. Wherein, the mass parts of each component are:

Polylactic acid: 100 parts

Plasticized starch: 26 parts

SBS: 18 copies

Vegetable fiber: 6 servings

Hydroxyl-terminated polylactic acid: 8.5 parts

Nanonaki montmorillonite: 4 parts

9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide: 10 parts

Melamine cyanurate: 5 parts

Antioxidant: 3 parts

Anti-ultraviolet agent: 3 parts.

The polylactic acid is poly-L-lactic acid, and the optimal molecular weight of the polylactic acid is 180000-400000 g/mol.

The plasticized starch is cornstarch plasticized by glycerin, and the quality of glycerin used for plasticization is 30% of the starch.

The plant fiber is chemically treated pine fiber, the diameter of which is between 400nm-1.5um and the aspect ratio between 20-500. The chemical method is an acid activation method after lye activation.

The molecular weight of the hydroxyl-terminated polylactic acid is between 40000-60000 g/mol, and the proportion of hydroxyl groups in the terminal groups to the total terminal group molar ratio is 80%.

The average wafer thickness of the nanometer sodium-based montmorillonite is less than 25nm, and commercially available nanometer sodium-based montmorillonite is used.

The 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide is a commercially available product.

The antioxidant is antioxidant 1010.

The anti-ultraviolet agent is ultraviolet absorber UVP-327.

The processing technology of the halogen-free flame-retardant biomass plate is:

1) All the raw materials were vacuum-dried at 50 degrees for 24 hours and set aside;

2) Blend all the raw materials in a high-speed mixer at 60 degrees for 8 minutes, and the speed is 180rad/min;

3) Put the blended raw materials into a screw extruder for melt extrusion, the melt extrusion temperature is 180-200 degrees, the screw speed is 200rad/min, and the residence time is 1.5 minutes.

The concrete performance data of embodiment 1,2 are as follows:

Composite properties Example 1 Example 2 Elongation at break (%) 64.5±5 69.6±5 Tensile strength (Mpa) 42.4±2.41 46.4±2.58 Impact strength (KJ/m ² ) 28.4±2.28 26.1±2.43 Oxygen Index(%) 30.2±1.2 28.4±1.2 vertical burn rating FV-0 FV-0

Claims (5)

1. a kind of halogen-free flameproof biomass board, by PLA, plasticized starch, SBS, string, hydroxyl-terminated polylactic acid, nanometer

It is sodium-based montmorillonite, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, melamine cyanurate, antioxidant, anti- Ultraviolet agent is constituted, wherein, the mass fraction of each component is：

PLA：100 parts

Plasticized starch：20-40 parts

SBS：10-20 parts

String：5-10 parts

Hydroxyl-terminated polylactic acid：5-10 parts

Nanometer sodium-based montmorillonite：3-6 parts

9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide：8-16 parts

Melamine cyanurate：4-8 parts

Antioxidant：2-4 parts

UV resistant agent：2-4 parts

It is further characterized in that：The molecular weight of the hydroxyl-terminated polylactic acid be 30000-100000g/mol between, hydroxyl ratio in end group Example accounts for total end group mol ratio between 70-90%, and the PLA is poly (l-lactic acid), poly- D-ALPHA-Hydroxypropionic acid or poly- L, D-ALPHA-Hydroxypropionic acid combination Thing, the molecular weight of the PLA is between 300000-500000g/mol.

2. a kind of halogen-free flameproof biomass board as claimed in claim 1, it is characterised in that：The plasticized starch is moulded for glycerine The cornstarch or tapioca of change, the qualities of glycerin for plasticizing is between the 20%-35% of starch.

3. a kind of halogen-free flameproof biomass board as claimed in claim 1, it is characterised in that：The string is through physics Or one kind in chemically treated bamboo fibre, wood-fibred, cotton fiber, bacterial fibers, its diameter is between 200nm-2 μm, length Footpath ratio is between 20-500.

4. a kind of halogen-free flameproof biomass board as claimed in claim 1, it is characterised in that：The antioxidant is antioxidant

One or more of arbitrary proportions mixing in BHT, antioxidant 1010, antioxidant 1076, antioxidant 164.

5. a kind of halogen-free flameproof biomass board as claimed in claim 1, it is characterised in that：The UV resistant agent is ultraviolet

One or more of arbitrary proportions mixing in light absorbers UV-531, UVP-327, UV-9, RMB.