TWI567103B - Process for the modification of biodegradable polymers - Google Patents

Description

Method for upgrading biodegradable polymers

The present invention relates to a process for upgrading a polymer or copolymer of the general structure having one or more repeating units: Wherein n is an integer, m is an integer in the range of 0 to 6, and R is selected from hydrogen, substituted or unsubstituted C ₁ -C ₂₀ alkyl, C ₃ -C ₂₀ cycloalkyl, C ₆ -C _{a 20} aryl group, a C ₇ -C ₂₀ aralkyl group, and a C ₇ -C ₂₀ alkaryl group, the groups may include a linear or branched alkyl moiety; wherein one or more substituents are selected A group consisting of a free hydroxyl group, an alkoxy group, a linear or branched alkane/alkenyl group, an aryloxy group, a halogen, a carboxylic acid, an ester, a carboxyl group, a nitrile and a guanamine group.

These polymers are generally biodegradable, meaning that they can be broken down by the action of naturally occurring microorganisms such as bacteria, fungi and algae.

The commercial potential of such (co)polymers is extremely high, especially due to their biodegradability and/or natural regenerability compared to petrochemically derived polymers. However, difficulties such as the poor melt strength of such (co)polymers during melt processing have hindered processing them into commercially attractive products. Several prior art documents disclose methods for modifying such (co)polymers to address such difficulties.

US 6,096,810 discloses the use of a free radical initiator such as an organic peroxide to modify a polyhydroxyalkanoate having the general structure shown above. The peroxides disclosed in this document are substantially linear and include 2,5-dimethyl-2,5-di(t-butylperoxy)hexane and 4,4-di(peroxide) Tributyl) butyl valerate.

WO 95/18169 discloses the modification of poly(hydroxy acids) such as polylactic acid by reactively extruding a polymer with an organic peroxide. The organic peroxides disclosed in this document are dilaurin peroxide, tert-butyl peroxydiacetate, tert-butyl peroxy-2-ethylhexanoate, and tert-butyl peroxyisobutyrate. Tert-butyl peroxyacetate, tert-butyl peroxybenzoate and dibenzoguanidine peroxide, all of which are linear in nature

No. 5,594,095 also discloses the modification of polylactic acid with a linear organic peroxide such as 2,5-dimethyl-2,5-di(t-butylperoxy)hexane and dicumyl peroxide.

Polymers modified according to such prior art methods produce only a low degree of branching or undergo gel formation due to cross-linking. Gel formation results in the appearance of "fish eyes" in the transparent film or coating or the generation of particles in the molding, which is clearly undesirable.

Surprisingly, it has now been found that if a cyclic organic peroxide modified (co)polymer is used, a (co)polymer having a combination of high degree of branching and no gel formation can be obtained.

Accordingly, the present invention relates to a method for upgrading a (co)polymer having one or more repeating units having the above-described general structure, the method involving making a (co)polymer and a ring The organic peroxide is contacted under conditions which cause at least some of the peroxide to decompose.

In addition, a high molecular weight distribution of the (co)polymer can be obtained, thereby improving its melt strength.

Another advantage of the process of the present invention is that unlike the peroxides used in the prior art, the cyclic organic peroxide used in the process of the present invention does not release the third butanol as a decomposition product. This absence of third butanol (due to its toxicological properties, it is not desired to be present in the (co)polymer for food related applications) makes the modified (co)polymers of the invention useful for foods involved In contact with the application.

The (co)polymer to be modified using the method of the present invention has the following general structure of one or more repeating units: Wherein n is an integer, m is an integer in the range of 0 to 6, and R is selected from hydrogen, substituted or unsubstituted C ₁ -C ₂₀ alkyl, C ₃ -C ₂₀ cycloalkyl, C ₆ -C _{a 20} aryl group, a C ₇ -C ₂₀ aralkyl group, and a C ₇ -C ₂₀ alkaryl group, the groups may include a linear or branched alkyl moiety; wherein one or more substituents are selected A group consisting of a free hydroxyl group, an alkoxy group, a linear or branched alkane/alkenyl group, an aryloxy group, a halogen, a carboxylic acid, an ester, a carboxyl group, a nitrile and a guanamine group.

Preferably, all of the repeating units in the (co)polymer satisfy the general structure shown above, but not all of the repeating units are the same. For example, a partially repeating unit may have a structure in which m=1 and R=ethyl, and another part of the repeating unit has a copolymer in which m=1 and R=methyl.

Examples of suitable (co)polymers include polylactic acid (PLA; m = 0 in the above structure, R = methyl), poly(3-hydroxybutyrate) (m = 1, R = methyl), polyglycolic acid (m=0, R=H), polyhydroxy-butyrate-co-valerate (m=1, R=ethyl) and poly(ε-caprolactone) (m=4, R=H).

The (co)polymers according to the above structure, either alone or in admixture with one or more other (co)polymers or materials, may be modified in the process of the invention. Suitable other (co)polymers are polyacrylates and polymethacrylates such as Ecoflex (a copolymer of 1,4-butanediol and terephthalic acid/adipic acid), a starch or starch derived polymer, a cellulose or cellulose derived polymer, and other natural (total) polymer.

A cyclic organic peroxide is defined as an organic molecule having a cyclic moiety and wherein the cyclic moiety contains a peroxide group. Cyclic organic peroxides suitable for use in the process of the invention include cyclic ketone peroxides and 1,2,4-trioxepane. Mixtures of one or more cyclic organic peroxides or a mixture of one or more cyclic organic peroxides with one or more acyclic organic peroxides may also be employed.

As shown in the examples below, the use of 1,2,4-trioxepane even increases the melt flow index of the resulting (co)polymer. This means that the melt processing characteristics of the resulting (co)polymer are improved, and this property is important if the polymer is to be treated by extrusion coating, fiber spinning or injection molding.

Preferably, the cyclic ketone is selected from the group consisting of the peroxides represented by Formulas I-III: Wherein R ₁ -R _{6 are} independently selected from hydrogen, C ₁ -C ₂₀ alkyl, C ₃ -C ₂₀ cycloalkyl, C ₆ -C ₂₀ aryl, C ₇ -C ₂₀ aralkyl, and C ₇ -C _a group of ₂₀ alkaryl groups, which may include a linear or branched alkyl moiety; and each of R ₁ -R ₆ may optionally be selected from one or more selected from the group consisting of hydroxyl, alkoxy, straight or Substituted groups of branched alkyl, aryloxy, ester, carboxyl, nitrile and decylamino groups.

The cyclic ketone is preferably composed of oxygen, carbon and hydrogen atoms. More preferably, the cyclic ketone is derived from a linear, branched or cyclic C ₃ -C ₁₃ ketone, most preferably a C ₃ -C ₇ ketone or a C ₄ -C ₂₀ diketone, most preferably a C ₄ -C ₇ diketone. The use of a ketone results in the formation of a cyclic ketone ketone of formula I and II, while the use of a diketone results in the formation of a cyclic ketone ketone of formula III.

Examples of cyclic ketones suitable for use in the process of the present invention include derivatives derived from acetone, etidylacetone, methyl ethyl ketone, methyl propyl ketone, methyl isopropyl ketone, methyl butyl ketone, Isobutyl ketone, methyl amyl ketone, methyl isoamyl ketone, methyl hexyl ketone, methyl heptyl ketone, diethyl ketone, ethyl propyl ketone, ethyl amyl ketone, methyl octyl Peroxides of ketones, methylmercapto ketones, cyclopentanone, cyclohexanone, 2-methylcyclohexanone, 3,3,5-trimethylcyclohexanone, and mixtures thereof.

A cyclic ketone can be prepared as described in WO 96/03397.

1,2,4-trioxepane is a peroxide having the formula: Wherein R ¹ , R ² , R ^{3 are} independently selected from hydrogen and substituted or unsubstituted hydrocarbon groups and wherein two of the groups R ¹ , R ² and R ³ are bonded as appropriate to form a ring structure.

Preferably, 1,2,4-trioxepane is a conditional 1,2,4-trioxepane wherein R ^{1-3 is} independently selected from hydrogen and substituted or unsubstituted a group of C ₁ -C ₂₀ alkyl, C ₃ -C ₂₀ cycloalkyl, C ₆ -C ₂₀ aryl, C ₇ -C ₂₀ aralkyl and C ₇ -C ₂₀ alkaryl groups, such groups A straight or branched alkyl moiety may be included, and two of the groups R ^1-3 may be joined to form a (substituted) cycloalkyl ring; wherein each of R ¹ -R ³ is optional or The plurality of substituents are selected from the group consisting of a hydroxyl group, an alkoxy group, a linear or branched alkane/alkenyl group, an aryloxy group, a halogen, a carboxylic acid, an ester, a carboxyl group, a nitrile, and a guanamine group.

R ¹ and R ^{3 are} preferably selected from the group consisting of lower alkyl groups, more preferably C ₁ -C ₆ alkyl groups such as methyl, ethyl and isopropyl groups, and methyl and ethyl groups are most preferred. R ^{2 is} preferably selected from the group consisting of hydrogen, methyl, ethyl, isopropyl, isobutyl, tert-butyl, pentyl, isopentyl, cyclohexyl, phenyl, CH ₃ C(O)CH ₂ - , C ₂ H ₅ OC(O)CH ₂ -, HOC(CH ₃ ) ₂ CH ₂ -, and Wherein R ^{4 is} independently selected from any of the group of compounds given for R ^1-3 . Another preferred 1,2,4-trioxepane is:

The (co)polymer can be contacted with the cyclic organic peroxide in a variety of ways, depending on the particular objectives of the upgrading process. The peroxide can be mixed with the melt of the (co)polymer, solid (in the form of a powder, chips, pellets, film or flakes) or solution.

In order to homogenize the (co)polymer with the peroxide, a conventional mixing device such as a kneader, a closed mixer or an extruder may be used. If the mixing is problematic for a particular substance, for example due to its high melting point, the surface of the solid (co)polymer may first be modified and subsequently melted and mixed. Alternatively, the (co)polymer can be first dissolved in a solvent and then allowed to react with the peroxide in solution.

The timing at which the peroxide and the (co)polymer are brought into contact with each other and the time at which the peroxide reacts with the (co)polymer can be selected independently of other conventional processing steps including introduction of additives, shaping, and the like. For example, the (co)polymer can be modified prior to introduction of the additive into the (co)polymer or after introduction of the additive. More importantly, the invention can be achieved during a (co)polymer forming step such as extrusion, extrusion coating, compression forming, thermoforming, foaming, blown filming, blow molding, injection molding or injection stretch blow molding. (Total) polymer modification. The polymer upgrading process of the present invention is preferably carried out in a press apparatus.

The amount of peroxide used in the process of the invention should, for example, be effective to achieve significant modification of the (co)polymer. Preferably, at least 0.005 wt%, more preferably at least 0.01 wt%, and most preferably at least 0.05 wt% of the cyclic organic peroxide, based on the weight of the (co)polymer, can be used. The amount of the cyclic organic peroxide is preferably less than 10% by weight, more preferably less than 5% by weight, and most preferably less than 1% by weight based on the weight of the (co)polymer.

Suitable conditions for at least some of the peroxide decomposition are preferably at least 180 ° C, more preferably at least 190 ° C, more preferably at least 200 ° C, more preferably at least 215 ° C, and most preferably at least 220 ° C. The temperature applied during the process of the present invention is preferably not higher than 260 ° C, more preferably not higher than 250 ° C, more preferably not higher than 240 ° C, more preferably not higher than 230 ° C, and most preferably not higher than 225 ° C.

After upgrading, the (co)polymer is cooled and/or devolatized using standard techniques in the polymerization industry.

The treatment time (i.e., the period of time from the moment the peroxide is contacted with the (co)polymer to the time of cooling or de-evaporating the modified (co)polymer) is preferably at least 5 seconds, more preferably At least 10 seconds, and most preferably at least 15 seconds. The treatment time is preferably no more than 15 minutes, more preferably no more than 10 minutes, more preferably no more than 5 minutes, more preferably no more than 60 seconds, and most preferably no more than 45 seconds.

The processing time required and the desired temperature are all dependent on the manner in which the peroxide and (co)polymer are in contact with each other. According to one embodiment of the invention, a cyclic organic peroxide is injected into the melt of the (co)polymer, for example, in an extruder. With this procedure, the processing time is preferably in the range of 5 to 60 seconds, more preferably 5 to 45 seconds. The temperature of the (co)polymer melt at the time of injection is preferably in the range of from 200 to 240 ° C, more preferably from 215 to 230 ° C, and most preferably from 220 to 225 ° C.

According to another embodiment, the (co)polymer and the cyclic organic peroxide are premixed and then introduced into a mixing device such as a kneader, a closed mixer or preferably an extruder. This embodiment may require a processing time of up to 15 minutes or more, preferably up to 10 minutes, more preferably up to 5 minutes. When present in a mixing device, the desired temperature of the mixture depends on its residence time in the device. The longer the residence time, the lower the temperature.

The (co)polymer may also contain additives during the upgrading. Preferred additives are catalyst inhibitors and slip agents and anti-sticking agents such as fatty guanamine. If necessary, stabilizers such as oxidative decomposition, thermal decomposition or UV decomposition inhibitors, lubricants, extender oils, pH control substances such as calcium carbonate, mold release agents, colorants, such as vermiculite, clay, chalk , carbon black and reinforcing or non-reinforcing fillers of fiber materials such as glass fiber, natural fiber, wood source materials, nucleating agents, plasticizers and accelerators.

The modified (co)polymers of the present invention can be used in a variety of applications, such as extrusion or blown film, for coatings (especially for coated paper or coated panels), such as bottles, beakers or trays. Foamed or molded articles, such as foamed trays for microwave or oven foods, clamshell grabs or other thermoformed articles, or injection molded discs.

Instance method

Melt flow index according to DIN 53735/ASTM 1238 (190 ° C, 21.6 N load) to G Ttfert The Melt Indexer of Model MP-D measures the Melt Flow Index (MFI). MFI is expressed in g/10 min.

Molecular Weight Characterization and Branching: The molecular weight of the modified (co)polymer was determined using a size exclusion chromatography (SEC) system consisting of the following: Pump: Knauer HPLC-Pump K501 Dissolvent: 1,1 , 1,3,3,3-hexafluoroisopropanol (HFIP) flow rate: 0.6 ml/min syringe: Spark Holland Triathlon autosampler, 50 μl concentration: approx. 2 mg/ml solvent: 1,1,1, 3,3,3-hexafluoroisopropanol column: 2×PSS PFG linear XL 7μ, 300×8 mm detection RI: Waters 410 differential refractor DP: Viscotek viscosity detector H502 LS: Viscotek RALLS detector

Self-light scattering (LS) detection calculates the molecular weight of the sample, that is, the number average (Mn), weight average (Mw), and Z average (Mz) molecular weight. The degree of dispersion (D) was calculated as Mw/Mn.

The intrinsic viscosity (IV) was measured using a viscosity detector.

From the Mark-Houwink plot, according to the theory of Zimm and Stockmayer, J. Chem. Phys. 17 (1949) 1301 calculates the number of branches (Bn, ie the average number of branches per molecule) and the frequency (λ, ie per 100 monomers Branch of the unit). The structural factor ε of the random branched polymer is 0.75.

Measurement of gel fraction Prior to analysis, the samples were dried overnight at 50 ° C in a circulating oven.

Procedure: Add 1 gram of sample and 50 ml of dichloromethane to a 50 ml crimp cap vial and cap the vial. The vial was shaken at room temperature for at least 10 hours.

Use B A chner funnel, a filtered Erlenmeyer flask and a water aspirator (providing suction to speed up the filtration process) was washed with 5 ml of dichloromethane (DCM) (Schleicher & Schuell No. 597, 45 mm).

The clean filter paper was placed on a petri dish, dried at 130 ° C for 1 hour, and cooled to room temperature in a desiccator. Petri dishes (including dry filter paper) were weighed.

Next, apply vacuum to B Chner funnel and pour the sample solution into the funnel. The filter paper including the residue was placed in a Petri dish again, dried at 130 ° C for 2 hours, and cooled to room temperature in a desiccator. The Petri dish containing the dried filter paper and the residue was weighed again and the weight of the residue was calculated.

The gel content is defined as the weight of the residue relative to the initial weight of the sample (1 gram). A gel fraction of less than 0.2 wt% indicates no gel formation.

Low Shear Viscometry The rheological measurements at low shear were performed at 180 °C using an AR2000 shear dynamic rheometer (TA Instruments) with the following specifications: Torque range CS: 0.1 μN. m to 200 mN. m speed range CS: 1E-8 to 300 rad/s inertia: ~15 μN. m ² frequency range: 1.2 E-7 to 100 Hz speed step change: <30 ms tension step change: <60 ms stress step change: <1 ms

Volatile measurement by GC static headspace analysis using Hewlett Packard HP5890 Series 2 GC, standard liquid injection and static headspace injection Combi-Pal (CTC Analytics, Switzerland) autoinjector and LabSystems' Atlas 2000 as data system To determine the volatiles in the modified polymer sample.

The following conditions were used: Column: Molten vermiculite, 25 m × 0.32 mm ID, coated with CP-Sil 5 CB, film thickness 5 μm, such as Chrompack carrier gas: helium, methane residence time: 62 seconds at 40 ° C Clock injector: Split-temperature: 150 ° C - shunt: 20 ml / min detector: flame ionization detector - temperature: 320 ° C detector sensitivity: range = 2 furnace temperature: initial: 40 ° C for 3 minutes. Rate 1: 5 ° C / min to 80 ° C Rate 2: 12 ° C / min Final: 300 ° C for 1 minute. Injection volume headspace (gas): 1.0 ml

One gram of the polymer sample was heated in a 20 ml jaw lid vial at 140 °C for 1 hour. A 1 ml vial of headspace material was then injected onto the GC column.

Example 1

Polylactic acid (PLA) pellets (HM1010, such as Hycail; MFI = 5.9 g/10 min) were added to the W&P ZSK30 extruder (L/D) using a Retsch vibrating trough placed on a KTRON 1 balance (to measure production) =36) Medium. The extruder has a screw speed of 200 rpm and a screw length of 1,150 mm.

The following temperature profile was used in the extruder: 200-240-240-240-240-240 °C.

Pure peroxide was injected into the polylactic acid melt at a screw length of 439 mm. Vacuum degassing begins at a screw length of 895 mm. Peroxide injection was carried out using a Knauer (Separations) 10 ml dosing pump with pressure readout and high pressure limit. The ingredient head is cooled with water.

Use three cyclic organic peroxides: Trigonox 301 (3,6,9-triethyl-3,6,9-trimethyl-1,4,7-triperoxydecane, such as Akzo Nobel) Trigonox 311 (3,3,5,7,7-pentamethyl-1,2,4-trioxepane, such as Akzo Nobel), and MEK-TP (3-ethyl-3,5,7, 7-tetramethyl-1,2,4-trioxepane)

Use four acyclic organic peroxides: Trigonox 101(2,5-Dimethyl-2,5-di(t-butylperoxy)hexane, such as Akzo Nobel) Trigonox 117 (t-butyl 2-ethylhexyl carbonate, such as Akzo Nobel) Trigonox 17(butyl-4,4-di(t-butylperoxy) valerate, such as Akzo Nobel) Trigonox C (T-butyl peroxybenzoate, such as Akzo Nobel)

Two amounts of peroxide were used, 0.25 wt% and 0.50 wt% in terms of polylactic acid.

The MFI, molecular weight distribution, number of branches and frequency, and gel fraction of the resulting modified polylactic acid were measured according to the procedure explained above. The results are presented in Tables 1 and 2 (where "Tx" stands for Trigonox ).

These tables show that the use of the cyclic organic peroxide of the present invention combines gel formation without molecular weight distribution broadening and branching. In addition, Trigonox 311 can increase the melt flow of the polymer.

Example 2

In addition to the polylactic acid used as a commercial grade such as Nature Works (MFI = 8.2 g/10 min), the temperature distribution in the extruder is 220/220/220/220/220/220 °C, and the peroxide tested is :Trigonox 301, Trigonox 311, Trigonox Example 1, except for a mixture of such peroxides (both 0.25 wt%) and MEK-TP.

The results are shown in Tables 3 and 4.

These tables again show that the use of the cyclic organic peroxide of the present invention combines gel formation without molecular weight distribution broadening and branching.

Further, the volatile matter remaining in the polylactic acid after being decomposed by the peroxide and remaining even after being volatilized in the extruder is detected according to the above method. The results are shown in Table 5.

This data shows that by using the cyclic organic peroxide of the present invention, the amount of volatiles remaining in the polymer, and especially the amount of acetone and third butanol, is significantly lower than when a linear peroxide is used. the amount.

In addition, the unmodified polymer was measured and 0.5 wt% Trigonox 301 and Trigonox The low shear viscosity of the 311 modified polymer.

The results are plotted as a graph in Figure 1, which shows that the process of the present invention produces a polymer having an increased low shear viscosity, thereby indicating an increase in chain kink caused by long chain branching.

Example 3

Example 2 was repeated except that the temperature distribution in the extruder was 210/210/210/210/210/210 °C.

The results are shown in Tables 6 and 7.

These tables confirm that the use of the cyclic organic peroxide of the present invention combines no gel formation with molecular weight distribution broadening and branching increase.

Example 4

Example 2 was repeated except that different polylactic acid grades such as Nature Works (MFI = 13.8 g/10 min) were used. The tested peroxide is a higher concentration (up to 1.0 wt%) of Trigonox 301.

The results are shown in Table 8.

The gel fraction of all samples was measured, indicating no gel formation.

The results in Table 8 indicate that the introduction of long chain branches results in an increase in Mw and an increase in Mz, which provides increased melt elasticity to the polymer.

The increase in the melt elasticity of the modified polymer was confirmed by measuring the storage modulus (G') and the loss modulus (G" in the oscillation frequency sweep. The result was plotted as the curve in Fig. 2.

At higher Trigonox The increase in storage modulus (G') at 301 wt% indicates an increase in melt elasticity.

In addition, the low shear viscosity of the unmodified polymer and the modified polymer was measured. The results are plotted as a curve in Figure 3, which shows that the method of the present invention produces an increased zero shear viscosity (as a result of higher Mw) and a "shear thinning" behavior in addition to enhanced melt elasticity (as a comparison) The result of high Mz/Mw, also known as polydispersity). With Trigonox These features are further enhanced by an increase of 301 wt%.

Figure 1 shows unmodified polylactic acid (PLA) and Trigonox used in accordance with the present invention 301 (Tx 301) and Trigonox The viscosity of the 311 (Tx 311) modified polylactic acid as a function of angular frequency.

Figure 2 shows the measured values of storage modulus (G') and loss modulus (G") in the oscillating frequency sweep of the unmodified polymer of Example 4 and the modified polymer.

Figure 3 shows the low shear viscosity of the unmodified polymer of Example 4 and the modified polymer.

Claims (9)

A modification method for upgrading a polymer or copolymer having the following general structure having one or more repeating units, Wherein n is an integer, m is an integer in the range of 0 to 6, and R is selected from hydrogen, substituted or unsubstituted C ₁ -C ₂₀ alkyl, C ₃ -C ₂₀ cycloalkyl, C ₆ -C _{a 20} aryl group, a C ₇ -C ₂₀ aralkyl group, and a C ₇ -C ₂₀ alkaryl group, the groups may include a linear or branched alkyl moiety; wherein the optional one or more substituents are Selecting a group consisting of a hydroxyl group, an alkoxy group, a linear or branched alkane/alkenyl group, an aryloxy group, a halogen, a carboxylic acid, an ester, a carboxyl group, a nitrile and a guanamine group, the method involving the polymer or copolymer The cyclic organic peroxide selected from the group consisting of cyclic ketones and 1,2,4-trioxepane is contacted under conditions which cause at least some of the peroxide to decompose. The method of claim 1, wherein the polymer or copolymer is contacted with the cyclic peroxide at a temperature in the range of from 180 to 260 °C. The method of claim 2, wherein the polymer or copolymer is contacted with the cyclic peroxide at a temperature in the range of from 200 to 240 °C. The method of any one of claims 1 to 3, wherein the cyclic peroxide is injected into the melt of the polymer or copolymer. The method of any one of claims 1 to 3, wherein the polymer is polylactic acid. The method of any one of claims 1 to 3, wherein the (co)polymer is stored It consists in a blend with one or more other (co)polymers or substances. A modified polymer or copolymer obtained by the method of any one of claims 1 to 6, which has the following general structure of one or more repeating units, Wherein n is an integer, m is an integer in the range of 0 to 6, and R is selected from hydrogen, substituted or unsubstituted C ₁ -C ₂₀ alkyl, C ₃ -C ₂₀ cycloalkyl, C ₆ -C _{a 20} aryl group, a C ₇ -C ₂₀ aralkyl group, and a C ₇ -C ₂₀ alkaryl group, the groups may include a linear or branched alkyl moiety; wherein the optional one or more substituents are A group consisting of a hydroxyl group, an alkoxy group, a linear or branched alkane/alkenyl group, an aryloxy group, a halogen, a carboxylic acid, an ester, a carboxyl group, a nitrile and a guanamine group is selected. A film, coating or article made from a modified polymer or copolymer as claimed in claim 7. A composition comprising (i) a polymer or copolymer having the general structure of one or more repeating units, Wherein n is an integer, m is an integer in the range of 0 to 6, and R is selected from substituted or unsubstituted C ₁ -C ₂₀ alkyl, C ₃ -C ₂₀ cycloalkyl, C ₆ -C ₂₀ aryl a C ₇ -C ₂₀ aralkyl group, and a C ₇ -C ₂₀ alkaryl group, which may include a linear or branched alkyl moiety; wherein the optional one or more substituents are selected from a group consisting of a hydroxyl group, an alkoxy group, a linear or branched alkane/alkenyl group, an aryloxy group, a halogen, a carboxylic acid, an ester, a carboxyl group, a nitrile and a guanamine group, and (ii) a cyclic ketone ketone and A cyclic organic peroxide of the group 1,2,4-trioxepane.