CN106496769B - A kind of homogeneous cross-linking method containing L-POSS cross-linking agent modified recycled PP and its preparation method - Google Patents

Abstract

A modified recycled PP containing L‑POSS crosslinking agent by homogeneous crosslinking method and its preparation method, which relate to a plastic material and its preparation method. The modification method of the present invention is: firstly, the recycled PP is heated at 80°C Under the condition of blowing and drying for 3-4 hours; put the self-made micro-crosslinking masterbatch into a universal pulverizer and then put it into a planetary ball mill to grind until the particle size of the crosslinking material reaches 10-50μm, and then weigh it according to the weight ratio. Take the dried recycled PP, self-made micro-crosslinking masterbatch, toughening agent, and inorganic filler and put them into a high-speed mixer and mix them for 4-6 minutes. Got recycled materials. The technical solution of the present invention can realize the effect of modifying PP with mechanical properties such as strengthening and toughening at the same time, and the introduction of the homogeneous cross-linking method can make the regeneration process of the modified PP without adding a compatibilizer and make the recycled material The performance is very good.

Description

A kind of homogeneous isomerism cross-linking method containing L-POSS cross-linking agent to modify and recycle PP and its preparation preparation method

technical field

The invention relates to a plastic material and a preparation method thereof, in particular to a modified and recycled PP containing an L-POSS crosslinking agent through a homogeneous crosslinking method and a preparation method thereof.

Background technique

Polypropylene is a thermoplastic resin produced by the polymerization of propylene. It is one of the lightest varieties of all plastics. It is non-toxic, odorless, tasteless, and has excellent surface stiffness, impact strength and scratch resistance. , and PP does not have the problem of environmental stress cracking, so polypropylene is widely used in the fields of packaging films, electrical equipment, and furniture.

With the expansion of the application field of polypropylene and the increase in the amount of use, the waste polypropylene is also increasing day by day. The waste polypropylene is aging and degraded, and its physical properties are far inferior to the virgin polypropylene. Its application is also greatly restricted. Used to make products with low performance. The recycling of waste polypropylene is more conducive to the sustainable development of the plastics industry. Recycling waste polypropylene to make polypropylene pipes can not only meet the market's demand for polypropylene pipes, but also solve environmental problems and save resources. Therefore, recycling and modification technology of waste polypropylene is fundamental to solve the above problems.

Recycling PP requires a cross-linking agent with excellent performance to modify it, so we synthesized a silane cross-linking agent containing L-POSS to modify it. L-POSS is a siloxane with a ladder structure. Its molecular structure is based on Si-O as the inorganic core, and a ladder-shaped network molecular structure formed by connecting Si-O bonds with larger bond energy and Si-C bonds. Composition, this molecular structure has good high temperature resistance and mechanical properties, the Si-H in its molecular structure can be combined with the vinyl group in the vinyl silane crosslinking agent to form a silane crosslinking agent containing L-POSS, due to this The cross-linking agent contains L-POSS and silane components at the same time, so this is a cross-linking agent with both properties, that is, a new type of cross-linking agent with high temperature resistance and cross-linking performance, which can meet the modification and recovery of PP.

Contents of the invention

The object of the present invention is to provide a kind of homogeneous cross-linking method containing L-POSS cross-linking agent to modify and recycle PP and its preparation method. Modification of recycled PP by method, so as to achieve the purpose of improving the mechanical properties of recycled PP, the process operation is simple and recycled plastics can be mass-produced to meet the industrialization requirements of the market and sustainable development.

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

A homogeneous cross-linking method containing L-POSS cross-linking agent modified recycled PP, containing the structural formula of L-POSS silane cross-linking agent is as follows:

.

A homoisomeric crosslinking method modified recycled PP containing L-POSS crosslinking agent, in parts by mass, comprising:

Recycle 100 copies of PP;

Toughening agent 3 to 10 parts;

10 to 30 parts of cross-linking masterbatch;

Inorganic filler 5-10 parts.

The homogeneous cross-linking method containing L-POSS cross-linking agent is used to modify and recycle PP, and the cross-linking masterbatch is composed of three parts: material A, material B and water generating agent;

A material composition: PP

Contains L-POSS silane crosslinking agent;

Initiator (dicumyl peroxide (DCP));

B material composition: PP

Catalyst (dibutyltin dilaurate);

Antioxidant (Antioxidant 1010);

Water generating agent ingredients: acid and metal oxides are mixed in a ratio of (1:1).

The described homogeneous cross-linking method containing L-POSS cross-linking agent modifies and recycles PP, and the described L-POSS silane cross-linking agent is obtained by adding L-POSS to vinyltrimethoxysilane The method of polymerization reaction, synthesized silane derivatives; the inorganic filler is at least one of calcium carbonate and talcum powder, preferably calcium carbonate; the initiator is benzoyl peroxide (BPO) and dicumyl peroxide (DCP ), preferably dicumyl peroxide.

The described homogeneous cross-linking method containing L-POSS cross-linking agent modifies and recycles PP, and the described toughening agent is at least one of POE, polyvinyl acetate emulsion, and polyvinyl alcohol, preferably POE The antioxidant is at least one of antioxidant 1010 and antioxidant 1076, preferably antioxidant 1010; the catalyst is dibutyltin dilaurate, triethylamine, tri-n-propylamine, tri-n-butylamine, N,N - At least one of dimethylbutylamine, preferably dibutyltin dilaurate; the water-generating agent is a mixture of acid and metal oxide in a certain proportion, preferably stearic acid and zinc oxide.

A method for preparing modified recycled PP containing L-POSS cross-linking agent through homogeneous cross-linking method, comprising the following steps:

A. Weigh 95 parts of material A according to the mass fraction, mix 4.5 parts of material B and put it into a twin-screw extruder to extrude and granulate, and then mix it with 0.5 part of water producing agent and put it into a twin-screw extruder to extrude Granulation to form micro-crosslinked masterbatch;

B. Put the micro-crosslinked masterbatch in Part A into a universal pulverizer and then put it into a planetary ball mill to grind until the particle size of the crosslinked material reaches 10-50 μm;

C. Dry the recycled PP at 80°C for 3-4 hours, put the micro-crosslinked masterbatch, toughening agent, recycled PP, and inorganic filler into the high-speed mixer according to the weight ratio, and mix at high speed for 4-6 minutes , to make it evenly mixed;

D. Add the homogeneously mixed material in the above-mentioned high-speed mixer to a twin-screw extruder with a screw length-to-diameter ratio of 36 and a rotating speed of 200r/min, and use the strong shear force of the twin-screw in the molten state to micro-crosslink the extruder. The average particle size of the masterbatch is controlled at 10-50 μm, and at the same time, the cross-linking material, toughening agent, recycled PP and inorganic filler are uniformly mixed, and the above-mentioned mixture is extruded and granulated to obtain recycled PP.

In the preparation method of modified recycled PP containing L-POSS cross-linking agent by homogeneous cross-linking method, the screw temperature of the twin-screw extruder is controlled between 160°C and 230°C.

Advantage and effect of the present invention are:

The strengthening and toughening modification of the present invention is an effective way to improve the mechanical properties of plastics. Its process operation is simple and recycled plastics can be mass-produced to meet the industrialization requirements of the market and sustainable development. Therefore, it aims at the defects of the prior art In the method, the purpose of improving the mechanical properties of the recovered PP is achieved by modifying and recovering PP by using a homogeneous isomeric cross-linking method containing an L-POSS cross-linking agent.

Description of drawings

Figure 1 is the equation for the synthesis of a new type of crosslinking agent by the reaction of L-POSS and vinyltrimethoxysilane.

Detailed ways

The present invention will be described in detail below in conjunction with examples.

Examples 1-3, the weight distribution ratio of each component in each embodiment is shown in Table 1. Weigh each component according to the proportion, mix it in a high-speed mixer for 5 minutes, and discharge the material. Put the raw material of the mixture into a twin-screw extruder to make the material. The temperature of the extruder is controlled between 160°C and 230°C. The rotating speed is 200r/min. Prepare the sample and test it according to the corresponding standard (see Table 2). The performance results are shown in Table 3.

Table 1: the formula composition (part) of embodiment 1-3

Table 2: Mechanical property test standard

Table 3: Mechanical property tests of PP recycled materials in Examples 1-3

From the performance test results of Examples 1-3 and Comparative Example 1 in Table 3, we know that: when no micro-crosslinking masterbatch is used, the addition of other modification additives will improve the impact performance of recycled PP while reducing the Tensile performance, and the particle size of the prepared micro-crosslinked masterbatch is crushed to 10-50μm, and then the crosslinked material, recycled PP, toughener, inorganic filler, etc. are put into the twin-screw extrusion with large aspect ratio In-machine shear mixing, this method can improve the toughness of recycled PP while also improving its tensile properties, and realizes the effect of simultaneously toughening and strengthening the modified PP by the homogeneous cross-linking method.

The present invention has been further described above through specific embodiments, but these embodiments are only exemplary and do not constitute any limitation to the protection scope of the present invention. Those skilled in the art understand that without departing from the spirit and scope of protection of the present invention, various equivalent replacements, modifications or improvements can be made to the technical solutions and implementations of the present invention, all of which should fall under the protection of the present invention. within range. The protection scope of the present invention shall be determined by the appended claims.

Claims (5)

1. A kind of homogeneous cross-linking method modification recovery PP containing L-POSS cross-linking agent, it is characterized in that, the structural formula containing L-POSS cross-linking agent is as follows: ; Containing L-POSS cross-linking agent The homogeneous cross-linking method modified recovery PP is calculated by weight and the raw material composition and content are as follows: Recycle 100 copies of PP; Toughening agent 3 to 10 parts; 10 to 30 parts of cross-linking masterbatch; Inorganic filler 5-10 parts; The cross-linked masterbatch is composed of A material, B material and water producing agent; A material composition: PP Contains L-POSS cross-linking agent; Initiator, described initiator is dicumyl peroxide DCP; B material composition: PP Catalyst, described catalyst is dibutyltin dilaurate; Antioxidant, described antioxidant is antioxidant 1010; Water generating agent ingredients: Acid and metal oxide are mixed in a ratio of 1:1. 2. A kind of homogeneous cross-linking method modification recovery PP containing L-POSS cross-linking agent according to claim 1, it is characterized in that, described L-POSS cross-linking agent is to use L-POSS and The silane derivative is synthesized by the addition polymerization reaction of vinyltrimethoxysilane; the inorganic filler is at least one of calcium carbonate and talcum powder. 3. A kind of homogeneous cross-linking method modification recovery PP containing L-POSS cross-linking agent according to claim 1, it is characterized in that, described toughening agent is POE, polyvinyl acetate emulsion, polyvinyl acetate at least one of vinyl alcohol. 4. a kind of preparation method that contains L-POSS cross-linking agent homogeneous cross-linking method modification recovery PP according to claim 1, is characterized in that, comprises the following steps: A. Weigh 95 parts of material A according to the number of parts by mass, mix 4.5 parts of material B and put it into a twin-screw extruder to extrude and granulate, and then mix it with 0.5 part of water producing agent and put it into the twin-screw extruder Extrusion granulation to form cross-linked masterbatch; B. Put the cross-linked masterbatch in step A into a universal pulverizer and then put it into a planetary ball mill to grind until the particle size of the cross-linked masterbatch reaches 10-50 μm; C. Dry the recycled PP at 80°C for 3 to 4 hours, put the crosslinking masterbatch, toughening agent, recycled PP, and inorganic filler into the high-speed mixer according to the weight ratio and mix at high speed for 4 to 6 minutes. make it evenly mixed; D. Add the homogeneously mixed material in the above-mentioned high-speed mixer into a twin-screw extruder with a screw length-to-diameter ratio of 36 and a rotating speed of 200r/min. The average particle size of the material is controlled at 10-50 μm. At the same time, the cross-linking masterbatch, toughening agent, recycled PP and inorganic filler are mixed evenly, and the above-mentioned mixture is extruded and granulated to obtain a homogeneous and heterogeneous product containing L-POSS cross-linking agent. Modification and recovery of PP by structural cross-linking method. 5. a kind of preparation method that contains L-POSS crosslinking agent homogeneous crosslinking method modification recovery PP according to claim 4, it is characterized in that: the screw temperature of described twin-screw extruder is controlled at Between 160°C and 230°C.