CN102199324A - Formula of linear polyethylene premix aid and preparation method thereof - Google Patents

Abstract

The invention relates to a formula of a linear polyethylene premix aid and a preparation method thereof. In the formula, the linear polyethylene premix aid comprises the following components of: 5 to 10 percent of full-vulcanizing silicon rubber, 4 to 5 percent of organic active silicon active flow aid, 5 to 10 percent of antioxidant 1076, 15 to 20 percent of antioxidant 168, 40 to 45 percent of silica gel 244, 5 to 10 percent of erucyl amide, 3 to 5 percent of antistatic agent 1800 and 3 to 5 percent of ultraviolet rays. The preparation method comprises the following steps of: 1) premixing and dispersing the components coarsely by utilizing a stirrer; 2) performing enhanced dispersion on the components by utilizing a ball grinding mill; and 3) performing the enhanced dispersion further on the components by utilizing a granulator during extrusion and granulation. In the linear polyethylene premix aid, various raw materials with the modified effect are premixed, and the formula design is optimized scientifically, so the problem of the compatibility of modified materials is better solved; and by the premix aid, the modified linear polyethylene has the multiple functions of smoothness, easiness in opening, high transparency, cleanness, stretching yield strength, breaking elongation and impact strength, high temperature resistance, low temperature resistance, aging prevention, static electricity resistance, ultraviolet ray prevention and the like, so the linear polyethylene premix aid is a composite product with high performance.

Description

A kind of linear polyethylene premix auxiliary formula and preparation method thereof

Technical field

The present invention relates to a kind of LLDPE premix auxiliary agent.

Background technology

Plastics-production of China and amount of finish have occupied the second place of the world, polyethylene (PE) output maximum in synthetic resins wherein, and with fastest developing speed, variety development is the most active.Because PE has good resistance to low temperature, chemical stability, anti-most of soda acid erosion performances, electrical insulation capability etc., again because it is in light weight, characteristics such as easy processing, the production of PE is able to fast development.Expecting gross domestic product in 2010 is 1,000 ten thousand tons, will reach more than 1,300 ten thousand tons by 2012.Wherein its density range of linear, low density PE (LLDPE) is identical with hp-ldpe, again because its molecular side chain is a short-chain branch, molecular structure is between the line style high-density and have between the hp-ldpe of long-chain branch, so its physical and mechanical properties is better than common new LDPE (film grade).The outer laminated film field that is widely used in the packing of food, medicine, cigarette and identity card, bank card etc.But homemade this class LLDPE PP Pipe Compound of just developing in recent years remains in following defective:

The one, the opening difficulty adhesion phenomenon appears, after making film; The 2nd, the transparency is not good enough, and mist degree is higher; The 3rd, resin itself is easily decomposed by photoxidation, thermooxidizing, ozone, easily degrades again under action of ultraviolet ray; The 4th, still need in certain Application Areas and to replenish the condition etc. that some function just can reach application.

Can overcome these above-mentioned drawbacks, realize its high-performance, the one, be taken at the performance of catalyzer to a great extent, promptly adopt the high performance PE product of the direct Development and Production of Polymer Synthesizing route.But this type of product technology difficulty of Development and Production is big, the cost of investment height, and the construction period is long, and the environmental protection treatment difficulty and is abroad compared, and at present domesticly also is in a backward condition.The 2nd, depend on the performance of auxiliary agent to a great extent, promptly utilize the method for adding auxiliary agent, overcome the self-defect of PE by modification, improve its some performance, be characterized in that investment is rare very fast, cost is low, does not almost have the environmental protection bottleneck, this shows the critical role that the new function auxiliary agent is occupied in the plastics industry.

But also there are more following problems usually in present homemade polyethylene auxiliary agent:

1, modified effect is general.At present a technical barrier of its maximum of modification of plastics is: if increase its rigidity then toughness reduce, if improve then rigidity deficiency of its toughness, its thermotolerance in addition, the key technical indexes such as stretchiness are also difficult to be improved synchronously.Usually adding a kind of premix auxiliary agent is difficult to address the above problem.

2, function singleness.Poly modification relates to all many-sides, smooth, easy opening, high transparent and anti-oxidant, antistatic, antiultraviolet or the like.But the auxiliary agent of some trades mark often only carries out modification at a binomial performance wherein at present.Want many-sided auxiliary agent that poly performance just need be added several different trades mark simultaneously that changes, not only increased production cost, also reduced efficiency simultaneously.

3, pulvis is more.Some trade mark products are still Powdered at present, have many drawbacks in process of production: easy airborne dust when easy wall built-up during as material stock, defeated material, easily stop up when reinforced, material loss is bigger, not only pollute, it is healthy to influence the workman, also make the metering misalignment, directly influence quality product, increase production cost.

Summary of the invention

What the present invention will solve is exactly the problems referred to above that existing LLDPE premix auxiliary agent exists, for people provide a kind of LLDPE premix auxiliary agent new formulation and preparation method thereof.

The present invention's prescription comprises following component:

Full sulphurated siliastic 5-10%

The active glidant 4-5% of organosilicon

Antioxidant 1076 5-10%

Oxidation inhibitor 168 15-20%

Silica gel 244 40-45%

Erucicamide 5-10%

Static inhibitor 1800 3-5%

UV light absorber 3-5%

The chemical name of above-mentioned organosilicon coagent is a methyl vinyl silicone rubber.

The chemical name of above-mentioned antioxidant 1076 is β-(4-hydroxyl-3.5-di-tert-butyl-phenyl) positive octadecyl ester of propionic acid.

The chemical name of above-mentioned oxidation inhibitor 168 is [three (2.4-two trimethylphenylmethane bases) phosphites.

The chemical name of above-mentioned static inhibitor 1800 is alkyl imidazoline (in add type).

The chemical name of above-mentioned UV light absorber is an O-hydroxyl-diphenyl ketone.

Above-mentioned prescription base reason is as follows:

(1) full sulphurated siliastic.Its particle diameter is in the 300-500nm interval, it is a system that is in cluster and macro object boundary zone of transition, its structure both had been different from the body block of material, also be different from single atom, special structure makes it have surface effects, volume effect, quantum tunneling effect or the like, have a series of novel physical and chemical property, my company has used this material and has contrasted proof after tested, and mechanical properties such as the shock strength of the LLDPE after improving auxiliary agent and using additive modification, tensile strength, heat resistance are significantly improved.

(2) the organosilicon activity helps fluidity (also claiming organo-silicic oil).Have the good transparency, smooth property and opening, it has a small amount of or micro-active group, can obviously improve resin flow after the interpolation, comprises that mold filling is easily and extrude moment and reduce; It is lubricated in having increased that to make that the demoulding is easy, discharging speed reaches product deformation soon little; Improved the consistency of filler and resin; The smooth finish and the hand sense of touch of product surface have been improved; The tensile strength and the shock strength of goods have been improved; Wear resistance, scratch resistance performance of goods etc. have been improved.

(3) antioxidant 1076, oxidation inhibitor 168.Oxidation inhibitor claims anti-aging agent again, is most widely used auxiliary agent in the plastics.Most widely used general one be meant that the polymerization of plastics is synthetic, granulation, storage, processing, use each different steps all to need the application of oxidation inhibitor.Next is meant that all types of plastic of various different molecular structures uses oxidation inhibitor all kinds of at most.Because organic materials is natural or synthetic all oxidizing reaction can take place, if polymkeric substance is oxidized, that not only makes their some mechanical properties, and for example tensile strength reduces, and the coarse injustice that the surface is become also can cause color change in plastic article.We have used two kinds of oxidation inhibitor in this masterbatch goods: the one, and the positive octadecyl ester of propionic acid is an auxiliary antioxidant, its action principle is by phosphorus or the valent variation of sulphur atom in self molecule, and highly active hydroperoxide decomposition among the PE is become the low activity molecule.The 2nd, pentaerythritol resin is main oxidation inhibitor, these product are white crystalline powder, nontoxic, harmless, pollution-free, nonflammable, indeformable, good volatility resistance, anti-extractable, resistance to migration are arranged, fabulous with the PE consistency, be one of kind the best in the high molecular resistance phenol oxidation inhibitor, it and the positive octadecyl ester oxidation inhibitor of propionic acid are also used, increased synergistic effect, made the performance of PE more stable.

(4) silica gel 244.Its particle diameter is usually between the 1000-3000 order.Be characterized in that chemical purity is higher, dispersing property is better, has cotton-shaped and netted accurate grain pattern, there is the hydroxyl of undersaturated residual bond and different bondings in the surface, has very high surfactivity, can improve mechanical properties such as the tensile strength of polymer materials and elongation at break.Secondly, can produce thin and hard projection as (film) surface at resin, thereby reduce contact area each other, reduce skin friction coefficient, thereby further improved the performance of film product opening.

(5) erucicamide.Its volatile performance is little, can be used as the slipping agent of high temperature process, the polyethylene of particularly suitable, and the time that is characterized in is long more, and the smooth performance of membrane product is good more.Not only smooth performance improves after the application, and the printing and the binding property of goods also had significant help.

(6) static inhibitor (in add type).Can effectively eliminate plastics because of rubbing and peeling off the electric charge accumulation that is produced, eliminate the disaster hidden-trouble that in use produces because of static sparking.

(7) ultraviolet ray (light) absorption agent.Can absorb influence, thereby make macromolecular material avoid the stablizer of photoaging the ultraviolet ray (light) of macromolecular material.Its base reason comprises: the efficient absorption ultraviolet ray, the UV light absorber behind the extinction becomes excited state, excites by making a variation mutually fast of hydrogen bond, thereby has avoided photochemical reaction, has effectively protected the aging of macromolecular material.

The operational path of auxiliary agent preparation method design of the present invention is: grind finely divided at a high speed and twin screw equipment blend extruding and pelletizing process but use the heat balls grinding machine.

Embodiment

Utilize stirrer that each component premix rough segmentation of the present invention is loose;

Utilize ball mill to the refinement dispersion again of each component;

Granulation and make each component further strengthen dispersion when utilizing tablets press to squeeze.

Annotate: this process flow diagram is seen Figure of description.

Process flow diagram CD-01 brief description:

The employed stirrer of step 1) is the tapered stirrer of cantilever duplex, and its technological operation Revolution Per Minute 90-120 changes, and the time is 60-90 minute.

Step 2) employed ball mill is a horizontal ball mill in, and its technological operation rotating speed is: per minute 60-90 changes, 75-80 ℃ of temperature control, and churning time is 60-80 minute.

In the step 3), employed is dual-screw pelletizer, and temperature is controlled in the 140-170 ℃ of scope, per hour 0.5 ton of technology controlling and process output.In addition, because of its work in-process retractility is stronger, temperature height and the too fast meeting of flow velocity make the pelletizing difficulty.Therefore the material temperature will be controlled in the 20-30 ℃ of scope during step 3) discharging.

Because raw material and final finished water absorbability are stronger.Therefore starting material are after airtight bag takes out, and throw in five minutes and use; Finished product is direct package encapsulation on production line, the environment that will keep dry in the workshop.

The present invention is mixed by the multiple starting material that will have modifying function, solved the problem of material compatibility well, make the present invention have ten remainder modification functions such as smooth, easy opening and high transparent, enhancing, toughness reinforcing, heat-resisting, stretch-proof, counter-bending, anti-oxidant, antistatic, antiultraviolet simultaneously, become a kind of multifunctional and composite type product.

Table 1 is a part physical index of the present invention:

Table 1:

Project	Index
		Outward appearance	The white particulate particle
Fugitive constituent, WT%	≤1.5

Total ash, WT%	4.0-7.0
		Tap density, g/L	450-530
Benzene insoluble, WT%	≤4.5

As shown in table 2, the present invention uses the twin screw granulating equipment and produces, and makes powder material through further being processed into particulate product, has reduced supplies consumption, has stablized quality product, has avoided pollution, has increased economic benefit.

Table 2:

Title	Waste
		Powdery product	2-3％
Granular product	0.1-0.5％

The applicant is used for petroleum chemical enterprise with the present invention LLDPE DFDA7042 (film-grade) is carried out modification, makes every performance index after the modification all above enterprise's top grade product standard, and table 3 is that part detects data:

Table 3: performance index contrasts on probation following (extracts trial report)

Test event	Standard index	Test result	Test result	Test result
					Lot number	(enterprise's top grade)	20090615A	20090616B	20090617C
Melt flow rate (MFR) (g/10min)	2.0	2.01	2.01	2.0
					Density g/cm 3	0.910-0.925	0.924	0.920	0.919
Mist degree %	26	22	21	21
					Tensile strength Mpa (vertically)	31.56	35.7	35.5	35.8
Tensile strength Mpa (laterally)	24.5	26.5	26.8	26.9
					Elongation % (vertically)	790	830	832	835
Elongation % (laterally)	880	910	912	911
					Puncture intensity J	2.84	2.95	2.98	2.97
Hammer falling impact strength g	95	98	99	97
					Intensity %≤	5	4.1	4.2	4
Opening	Be easy to opening	Be easy to opening	Be easy to opening	Be easy to opening

Compare jointly through my company and user in addition, resin and film are placed two weeks and are not found phenomenons such as oily, bloom, flavescence; Resin film is preserved after three months and the contrast of seven days product of production, transparency, smooth property and skin friction coefficient indifference.

From the data of table 3 as can be seen, DFDA7042 trade mark LLDPE is added a spot of CD-9# premix auxiliary agent can make main mechanical performance index improve synchronously, has reached the standard of engineering plastics.

The present invention will be further described below in conjunction with embodiment:

Each component is allocated in following ratio, and its process operation parameter is constant, makes with product and tries out contrast through repeated detection and user, thinks and implements second group of formula ratio for best, so finally select example 2 assembly sides for determining prescription.

Sequence number	Title	Unit	Example 1	Example 2	Example 3
						1	Full sulphurated siliastic	％	5	5	5
2	The active glidant of organosilicon	％	4	5	5
						3	Antioxidant 1076	％	10	10	10
4	Oxidation inhibitor 168	％	16	20	20
						5	Silica gel 244	％	45	45	40
6	Erucicamide	％	10	10	10
						7	Static inhibitor	％	5	3	5
8	UV light absorber	％	5	2	5

Claims (6)

1. linear polyethylene premix auxiliary formula, its feature comprise and the ratio of each component is:

Full sulphurated siliastic 5-10%

The active glidant 4-5% of organosilicon

Antioxidant 1076 5-10%

Oxidation inhibitor 168 15-20%

Silica gel 244 40-45%

Erucicamide 5-10%

Static inhibitor 1800 3-5%

UV light absorber 3-5%.

2. claim: a kind of preparation method of linear polyethylene premix auxiliary agent, its feature comprises the steps:

1) utilize stirrer that each component premix rough segmentation of the present invention is loose;

2) utilize ball mill to the refinement dispersion again of each component;

Make each component further strengthen dispersion when 3) utilizing the tablets press extruding pelletization.

3. the preparation method of a kind of linear polyethylene premix auxiliary agent as claimed in claim 2 is characterized in that the employed stirrer of step 1) is the cantilever twin-shaft mixer, and its technological operation rotating speed is: per minute 90-120 changes, and churning time is 60-90 minute.

4. the preparation method of a kind of linear polyethylene premix auxiliary agent as claimed in claim, it is characterized in that step 2) in employed ball mill be horizontal ball mill, its technology controlling and process rotating speed changes for per minute 60-90,75-80 ℃ of its technological temperature control, and the time is 60-80 minute.

5. after disperseing to finish as the claim refinement, raw material is imported extruding pelletization reinforcement dispersion in the dual-screw pelletizer, temperature is controlled at 140-170 ℃ of scope, per hour 0.5 ton of process flow rate output.In addition because of its work in-process retractility is stronger, the too high and too fast meeting of flow velocity of temperature makes the pelletizing difficulty, so temperature will be controlled in the 20-30 ℃ of scope during discharging.

6. the preparation method of polyethylene auxiliary agent as claimed in claim 2 because raw material and product water absorbability are stronger, is characterized in that starting material after sealing bag takes out, and throws in 5 minutes and uses; Finished product is direct package encapsulation on production line, will keep than the exsiccant environment in the workshop.

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