CN114933888A

CN114933888A - Hot-melt pressure-sensitive adhesive capable of being coated at high speed and preparation method thereof

Info

Publication number: CN114933888A
Application number: CN202210470294.9A
Authority: CN
Inventors: 张飞宇; 谌小斑; 郝晓鹏; 李其豪
Original assignee: Zhejiang Guanhao New Material Co ltd
Current assignee: Zhejiang Guanhao New Material Co ltd
Priority date: 2022-04-28
Filing date: 2022-04-28
Publication date: 2022-08-23

Abstract

The invention discloses a high-speed coating hot-melt pressure-sensitive adhesive and a preparation method thereof, and the high-speed coating hot-melt pressure-sensitive adhesive comprises the following raw materials, by weight, 15-60 parts of a thermoplastic elastomer, 30-70 parts of a tackifying resin, 10-30 parts of a plasticizer and 0.3-1.2 parts of an antioxidant. The method has the following beneficial effects: the preparation process of the high-speed coatable hot-melt pressure-sensitive adhesive is simple, the fluidity is good, and the coating speed of 450m/min can be met.

Description

Hot-melt pressure-sensitive adhesive capable of being coated at high speed and preparation method thereof

Technical Field

The invention relates to the technical field of pressure-sensitive adhesives, in particular to a hot-melt pressure-sensitive adhesive capable of being coated at a high speed and a preparation method thereof.

Background

The existing hot-melt pressure-sensitive adhesive has the characteristics of high solid content and low VOC (volatile organic compound), is widely applied to the fields of labels, packaging, medical treatment and sanitation, non-setting adhesive and the like, and has the characteristics of low cost and environmental friendliness, and can effectively replace the traditional solvent type pressure-sensitive adhesive and partial emulsion type pressure-sensitive adhesive. Along with the increasing perfection of the field of electronic commerce, the commercial label is more and more in demand, and the requirements on the coating speed and the die cutting processability of the hot-melt pressure-sensitive adhesive are increased.

Patent CN201610613117.6 provides a cold-stored hot melt adhesive composition for label, and when the label is pasted, unit coating weight is few, and production efficiency is high, and the laminating performance is excellent, and colloid cohesive strength is big, and it is excellent to resist the oil permeability, and weatherability is good, and it includes following component: 15-25% by weight of a first thermoplastic rubber, and a second thermoplastic rubber: 10-15% (weight percentage), plasticizer: 15-25% (weight percent), first tackifying resin: 20-30 percent (weight percentage), 20-30 percent (weight percentage) of second tackifying resin and 1.0 percent (weight percentage) of antioxidant, and the invention also provides a preparation method of the hot melt adhesive composition for the refrigerated label.

However, in the prior art, the coating speed and the die cutting processing performance of the pressure-sensitive adhesive in the coating process are higher and higher, and if the cohesive strength of the colloid formula is high, particularly the commercially available hot-melt pressure-sensitive adhesive for the high-viscosity label needs to ensure good initial viscosity and permanent viscosity, the problem of high melt viscosity of the glue exists, and the coating speed cannot be increased finally. Moreover, with the improvement of the technology of coating equipment and die cutting waste discharge equipment, the running vehicle speed is higher and higher, in addition, the application range of hot glue labels is wider and wider, the original commercial glue is difficult to meet the comprehensive requirements in the aspects of high-speed coating, high-speed die cutting waste discharge and labeling, and especially in the running vehicle speed, the defects of thick and thin material lines, coating omission points or lines and the like can be generated when the conventional commercial glue exceeds the limited vehicle speed of 360m/min, so that the further improvement of the running efficiency is limited.

In conclusion, the invention provides the high-speed coating hot-melt pressure-sensitive adhesive and the preparation method thereof, and the high-speed coating hot-melt pressure-sensitive adhesive is simple to prepare, has good fluidity and can meet the coating speed of 450 m/min.

Disclosure of Invention

The invention aims to provide a high-speed coating hot-melt pressure-sensitive adhesive and a preparation method thereof, wherein the high-speed coating hot-melt pressure-sensitive adhesive is simple to prepare, has good fluidity and can meet the coating speed of 450 m/min.

In order to achieve the purpose, the invention is realized by the following technical scheme:

the hot-melt pressure-sensitive adhesive capable of being coated at high speed comprises, by weight, 15-60 parts of a thermoplastic elastomer, 30-70 parts of a tackifying resin, 10-30 parts of a plasticizer and 0.3-1.2 parts of an antioxidant.

As a further improvement of the scheme, the thermoplastic elastomer is one or a mixture of more selected from SIS, SBS, SEBS and SEPS.

As a further improvement of the scheme, the molecular structure of the thermoplastic elastomer can be any one or two of star-shaped structure and linear structure.

As a further improvement of the scheme, the melt flow rate of the thermoplastic elastomer is 10-30 g/10min

In a further improvement of the scheme, the diblock fraction of the thermoplastic elastomer is 20-30%, and the block ratio is 20/80-30/70

As a further improvement of the scheme, the tackifying resin is one or a mixture of more of terpene resin, petroleum resin (C5, C9, C5/C9 copolymer), coumarone resin, rosin resin and modified or derivative thereof.

As a further improvement of the scheme, the plasticizer is any one or a mixture of several selected from naphthenic oil, paraffin oil, white oil, phthalate esters and low molecular weight polytetramethylene glycol.

As a further improvement of this embodiment, the antioxidant is a mixture of pentaerythritol tetrakis (3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate) and tris (2, 4-di-tert-butylphenyl) phosphite, and the antioxidant is pentaerythritol tetrakis (3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate) and tris (2, 4-di-tert-butylphenyl) phosphite in a weight ratio of 2: 1.

A method for preparing a hot-melt pressure-sensitive adhesive capable of being coated at high speed comprises the following preparation steps:

s1, weighing the components according to the proportion, wherein the solution polymerized styrene butadiene rubber is crushed for standby;

s2, putting the weighed plasticizer into a reaction kettle, stirring and heating the plasticizer to 120-130 ℃, and adding an antioxidant;

s3 was stirred for 10 minutes until no significant antioxidant particles were in the kettle, and then the thermoplastic elastomer was added slowly. Controlling the temperature in the reaction kettle to be 145-155 ℃, vacuumizing to the vacuum degree of 0.085MPa, and continuously stirring until the thermoplastic elastomer is a uniform mixture;

s4, adding tackifying resin into the reaction kettle, controlling the temperature in the reaction kettle to be 145-155 ℃, vacuumizing to the vacuum degree of 0.085MPa, increasing the stirring speed, stirring until the glue becomes a uniform and transparent mixture, and finally discharging the glue.

The hot-melt pressure-sensitive adhesive capable of being coated at high speed has the following beneficial effects:

the hot-melt pressure-sensitive adhesive for high-speed coating improves the fluidity of the hot-melt pressure-sensitive adhesive, reduces the viscosity of the hot-melt pressure-sensitive adhesive, maintains good cohesive strength and obtains good high-speed coating performance by changing the types and the proportions of different thermoplastic elastomers;

after being prepared into the self-adhesive label, the hot-melt pressure-sensitive adhesive has the advantages of good initial adhesion, high peel strength and good adhesive holding capacity, has excellent die cutting performance, and can be used for coating the self-adhesive label at high speed;

the solution-polymerized styrene butadiene rubber block-type thermoplastic elastomer has the characteristics of good weather resistance, good rebound resilience and the like, can reduce the viscosity of a formula and the modulus of glue when added into the formula, and improves the fluidity at high temperature and the wettability on different substrates;

the rubber provides an adhesive main body frame, the adhesive provides the basis of final viscosity, weather resistance and mechanical property, and the tackifying resin is the other most important component in the pressure-sensitive adhesive except the main body elastomer. Softening agent: the modulus of the formula is reduced, the fluidity and the wettability of the glue are improved, and the antioxidant is as follows: the rubber and the resin are protected, thermal oxidation is prevented at high temperature, and finally all components are in synergistic effect, so that the hot-melt pressure-sensitive adhesive disclosed by the invention has good fluidity and can meet the requirement of coating speed of 450 m/min.

Detailed Description

In order to make the purpose, technical scheme and advantages of the invention clearer, the invention is further described with reference to embodiments 1 to 3 as follows:

s3 was stirred for 10 minutes until no significant antioxidant particles were present in the kettle, and the thermoplastic elastomer was added slowly. Controlling the temperature in the reaction kettle to be 145-155 ℃, vacuumizing to the vacuum degree of 0.085MPa, and continuously stirring until the thermoplastic elastomer is a uniform mixture;

s4, adding tackifying resin into the reaction kettle, controlling the temperature in the reaction kettle to 145-155 ℃, vacuumizing to 0.085MPa, increasing the stirring speed, stirring until the glue becomes a uniform transparent mixture, and finally discharging the glue.

Example 1

The hot-melt pressure-sensitive adhesive in the embodiment comprises the following components in parts by weight: 30 parts of thermoplastic elastomer, 120 parts of tackifying resin, 220 parts of tackifying resin, 310 parts of tackifying resin, 19 parts of plasticizer and 1 part of antioxidant.

The thermoplastic elastomer in this example is SIS, where the thermoplastic elastomer has a melt flow index of 17g/10min, a diblock fraction of 15%, and a block ratio of 28/72;

the tackifying resin 1 of the present example is a C5 petroleum resin, wherein the softening point of the C5 petroleum resin is 95 ℃;

the tackifying resin 2 of the present example is a styrene-modified C5 petroleum resin, wherein the softening point of the styrene-modified C5 petroleum resin is 95 ℃;

the tackifying resin 3 of the present example is a modified rosin resin, wherein the modified rosin resin has a softening point of 90 ℃;

the plasticizer in the embodiment is naphthenic oil KN-4010;

the antioxidant described in this example was a mixture of pentaerythritol tetrakis (3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate) and tris (2, 4-di-tert-butylphenyl) phosphite in a weight ratio of 2: 1.

Example 2

In the embodiment, the hot-melt pressure-sensitive adhesive comprises the following components in parts by weight: 30 parts of thermoplastic elastomer, 120 parts of tackifying resin, 220 parts of tackifying resin, 310 parts of tackifying resin, 19 parts of plasticizer and 1 part of antioxidant.

The thermoplastic elastomer described in this example is a blend of SIS and SBS with a thermoplastic elastomer melt flow index of 22g/10min, a diblock fraction of 21%, and a block ratio of 22/78;

the plasticizer in the embodiment is naphthenic oil KN-4010;

That is, embodiment 2 differs from embodiment 1 only in that:

in the formulation components of the hot melt pressure sensitive adhesive, the thermoplastic elastomer of example 1 is replaced by a mixture of SIS and SBS, the weight ratio of SIS to SBS is 2:1, wherein the melt flow index of the mixture of SIS and SBS is 22g/10min, the diblock fraction is 21%, the block ratio is 22/78, and the rest of the raw materials and the amount are the same as in example 1.

Example 3

the tackifying resin 1 of the present example is a terpene resin, wherein the terpene resin has a softening point of 95 ℃;

the plasticizer in the embodiment is naphthenic oil KN-4010;

That is, embodiment 2 differs from embodiment 1 only in that:

hot melt pressure sensitive adhesive tackifying resin 1 of example 1 was replaced with a terpene resin having a softening point of 95 ℃.

The remaining raw materials and the amounts used were the same as in example 1.

Example 4

In the hot melt pressure sensitive adhesive of this example, tackifying resin 2 of example 1 was replaced with tall oil rosin resin, which has a softening point of 90 ℃.

Example 5

In the embodiment, the hot-melt pressure-sensitive adhesive replaces the thermoplastic elastomer in the embodiment 2 with a mixture of SIS and SBS, wherein the weight ratio of SIS to SBS is 2:1, the melt flow index of the mixture of SIS and SBS is 22g/10min, the diblock fraction is 30%, and the block ratio is 22/78;

the remaining raw materials and the amounts used were the same as in example 2.

Example 6

In the embodiment, the hot-melt pressure-sensitive adhesive replaces the thermoplastic elastomer in the embodiment 5 with a mixture of SIS and SBS, the weight ratio of SIS to SBS is 2:1, wherein the melt flow index of the mixture of SIS and SBS is 29g/10min, the diblock fraction is 30%, and the block ratio is 22/78;

the remaining raw materials and the amounts used were the same as in example 2.

Example 7

In the embodiment, the hot-melt pressure-sensitive adhesive replaces the thermoplastic elastomer in the embodiment 6 with a mixture of SIS and SBS, wherein the weight ratio of SIS to SBS is 2:1, the melt flow index of the mixture of SIS and SBS is 29g/10min, the diblock fraction is 30%, and the block ratio is 29/71;

the remaining raw materials and the amounts used were the same as in example 2.

Example 8

In the embodiment, the hot-melt pressure-sensitive adhesive replaces the thermoplastic elastomer in the embodiment 2 with a mixture of SIS and SBS, the weight ratio of SIS to SBS is 3:1, wherein the melt flow index of the mixture of SIS and SBS is 22g/10min, the diblock fraction is 21%, and the block ratio is 22/78;

the other raw materials and the amounts thereof were the same as in example 2

Comparative example 1

The hot-melt pressure-sensitive adhesive in the comparative example comprises the following components in parts by weight: 65 parts of thermoplastic elastomer, 110 parts of tackifying resin, 210 parts of tackifying resin, 14 parts of plasticizer and 1 part of antioxidant.

The specific composition of the contained raw materials was the same as in example 1 (except that the specific composition was contained in parts by weight different from that in example 1, and further, comparative example 1 did not contain tackifier resin 3).

Comparative example 2

Comparative example 2 differs from example 1 only in that: hot melt pressure sensitive adhesive the thermoplastic elastomer SIS of example 1 was replaced by SIS with a melt flow index of 5g/10 min.

The other raw materials and the amounts thereof were the same as in example 1

Comparative example 3

Comparative example 3 differs from example 1 only in that: the hot melt pressure sensitive adhesive was prepared by adjusting the plasticizer to 8 parts and the tackifier resin to 3 parts in example 1 to 15 parts.

The other raw materials and the amounts thereof were the same as in example 1

After the glue of the embodiments 1-8 and the comparative examples 1-3 is prepared, injecting the glue into coating equipment, coating the glue on release paper in a slit manner, compounding the glue with a surface layer, and rolling to obtain a label material; carrying out operation, mechanical property, labeling and die cutting tests on the label material;

initial adhesion, permanent adhesion, 170 ℃ viscosity, 450m/min coating test were carried out, and the results are shown in the following table:

TABLE 1 Performance test results for examples 1-8 and comparative examples 1-3

The comparison of the embodiment 1, the embodiment 2 and the embodiment 8 shows that the addition of SBS can increase the cohesive strength, reduce the annular initial adhesion and increase the viscosity;

comparing example 3 with example 2, it can be seen that the terpene resin can improve the ring initial adhesion and cohesive strength of the glue, and increase the viscosity at the same time;

example 4 illustrates that different types of tackifying resins of the same type still have an effect on the viscosity of the glue;

comparing example 5 with example 2, it is seen that the diblock fraction increases initial viscosity, cohesive strength decreases, and viscosity decreases;

comparing example 6 with example 2, it can be seen that the melt flow index is increased, the initial viscosity is increased, the cohesive strength is reduced, and the viscosity is reduced;

the comparison between example 7 and example 2 shows that the block ratio is increased, the initial viscosity is reduced, the cohesive strength is increased, and the viscosity is reduced;

comparing comparative example 1 with example 1, it can be seen that the part of the thermoplastic elastomer is too large, the colloid viscosity is reduced, and the viscosity is increased;

comparing the comparative example 2 with the example 1, it can be seen that the thermoplastic elastic melt flow index is too low, and the viscosity is increased;

comparison of comparative example 3 with example 1 shows that the amount of plasticizer is too low, the viscosity of the gel decreases, and the viscosity increases.

From the test results of the above examples 1 to 8 and comparative examples 1 to 3, the hot melt pressure sensitive adhesive of the present invention capable of being coated at high speed has the following beneficial effects:

according to the hot-melt pressure-sensitive adhesive for high-speed coating, the types and the proportions of different thermoplastic elastomers are changed, so that the fluidity of the hot-melt pressure-sensitive adhesive is improved, the viscosity of the hot-melt pressure-sensitive adhesive is reduced, good cohesive strength is maintained, and good high-speed coating performance can be considered;

table 2 example 3 test results after preparation of labels from hot melt adhesives

Item	Index (I)	Unit of	Detection method
				Surface layer	80g coated paper
Coating amount of glue	16±1.0	g/m ²
				Initial adhesion	20～24	N	FTM9，ss
90 degree peel force (20min)	10 or paper tear	N/25mm	FTM2，ss
				Permanent adhesion		H	FTM8，st
Coating vehicle speed	450	m/min
				Die cutting vehicle speed	120	m/min

As can be seen from Table 2, the hot melt pressure sensitive adhesive of the invention has the advantages of good initial adhesion, high peel strength and good adhesive holding capacity after being prepared into a self-adhesive label, has excellent die cutting performance, and can be used for coating the self-adhesive label at high speed.

The above description is only for the preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all equivalent modifications made by the present invention are within the scope of the present invention.

Claims

1. The hot-melt pressure-sensitive adhesive capable of being coated at high speed is characterized by comprising, by weight, 15-60 parts of thermoplastic elastomer, 30-70 parts of tackifying resin, 10-30 parts of plasticizer and 0.3-1.2 parts of antioxidant.

2. The hot-melt pressure-sensitive adhesive capable of being coated at high speed according to claim 1, wherein the thermoplastic elastomer is one or a mixture of SIS, SBS, SEBS and SEPS.

3. The hot-melt pressure-sensitive adhesive capable of being coated at high speed according to claim 2, wherein the molecular structure of the thermoplastic elastomer can be any one or two of star-shaped structure and linear structure.

4. The hot-melt pressure-sensitive adhesive capable of being coated at a high speed according to claim 2, wherein the melt flow rate of the thermoplastic elastomer is 10-30 g/10 min.

5. The hot melt pressure sensitive adhesive capable of being coated at high speed according to claim 2, wherein the diblock fraction of the thermoplastic elastomer is 20-30%, and the block ratio is 20/80-30/70.

6. The hot melt pressure sensitive adhesive capable of being coated at high speed according to claim 1, wherein the tackifying resin is any one or a mixture of terpene resin, petroleum resin (C5, C9, C5/C9 copolymer), coumarone resin, rosin resin and modified or derivative thereof.

7. The hot melt pressure sensitive adhesive capable of being coated at high speed according to claim 1, wherein the plasticizer is any one or a mixture of several selected from naphthenic oil KN-4010, paraffin oil, white oil, phthalate esters and low molecular weight polytetramethylene glycol.

8. A high speed coatable hot melt pressure sensitive adhesive according to claim 1, wherein the antioxidant is a mixture of pentaerythritol tetrakis (3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate) and tris (2, 4-di-tert-butylphenyl) phosphite and the weight ratio of pentaerythritol tetrakis (3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate) to tris (2, 4-di-tert-butylphenyl) phosphite is 2: 1.

9. A method for preparing the hot melt pressure sensitive adhesive capable of being coated at high speed according to any one of claims 1 to 8, which is characterized by comprising the following preparation steps: